From your post it sounds like you need a more interesting job, not a PhD. You don't want any of the things a PhD brings you, intrinsically or extrinsically.

Have you talked to Oxford's career service people? It looks like you're still able to get a career advice appointment with them if it's been less than two years since you graduated.

@BryanKrause I would love to have an interesting job that hopefully pays well, but so far I seem to not have any luck with it. It seems to me that in UK for industries that sound interesting to me (data science, security, quant research) all of their junior hires come from 2nd year internships and all of the senior positions come from within the industry. It genuinely feels like me having missed out on internships/grad placements made these careers unavailable to me.

@user176372 I have several times and they are mostly not very helpful if I'm completely honest. It does not help that I have no idea what I actually want to do with my life; all I know is not this and most likely not academia.

Could you apply to a PhD in a field that uses CS and Math but has more industry applications, like formal methods or cryptography? I know there are companies hiring these people, not many but I assume more than those hiring quantum computing researchers.

Reading this post and the OP's comment below, there's this: Scratch almost every adult and you'll find traces of variations on "I deserve better than this..." You can spend your time bemoaning the ecosystem in which you find yourself, or you can use your talents, and develop other talents, in order to plow your own furrow. If you're sure you can do better, then every obstacle is, in fact, an opportunity and every setback a valuable lesson to be assimilated. Never forget, though, to "mind the step". A very few mavericks thrive, but most crash-and-burn and are forgotten.

When it comes to hindsight, we all have 6/6 (aka "20/20") vision... Project yourself 5 or 10 years into the future and look back to the present. Assess your strengths and weaknesses (honestly!) from that vantage point, and how those exist in the current environment. "See!" those hidden opportunities (aka "stepping stones") that you currently don't even consider worth thinking about ("takes too long", "costs too much", "unlikely") and plot a path forward. Battles are won by generals who make use of their resources, and lost by those who bemoan "lack of" or "all the wrong" resources...

When you first started searching for industry jobs you suffered from lack of experience. How has this changed now that you have 1 job under your belt? Have you tried applying for industry positions again?

Also note that "teaching 5 classes just to survive" is not the reality of academic positions in the UK. Everyone complains about too much teaching; that's universal everywhere. I teach an equivalent of 1.3 modules per academic year. The starting early career salary is well over the 30k a year that you mention, and higher at Russel group Unis. And most people chose to stay in academia rather than go to industry specifically so that they could work on problems they find interesting, with comparatively fewer limitations than in industry.

Have you applied for jobs at FAANG (Amazon, Google, Facebook, IBM, Microsoft, etc...) ? Those big tech companies will certainly have many research and development jobs related to software development and engineering that are more challenging for you. --- In addition, Google and IBM do have many big projects on quantum computer. You can google search to find more info about these projects.

You can also take a few more courses in AI, ML, etc... at Oxford. Those are pretty much in high demand in IT right now. Quantum computer jobs are great, but right now, there are a lot more jobs in AI and ML than in quantum computer in the IT industry.

You enjoyed Quantum Computing at Oxford, got a 1st in MATHS, of all subjects. And now you sound all doom and gloom. Do you think it might be worth talking to a psychologist or a therapist? There might some things like depression or anxiety which sneak up on you.

@schrödingcöder If depression or anxiety was significantly involved in his failing to get interviews for interesting and challenging jobs in industry, he'd be less likely still to have won over the dons of Cambridge. The answer must therefore lie elsewhere. I can understand staff at the Oxford Careers Office not raising the more likely cause of his disfavor: it's not their job to break hard news to young guys nor face the flak for doing so while the dons dodge the manly work. His low morale is just a consequence of his situation now and the need of people of his age to be usefully engaged.

@Trunk I did a PhD in a Maths department in the UK, and there was a whole spectrum of people there. And some Cambridge dons whom I met weren't necessarily the most switched-on to non-academic things. I'm not an MD, but from personal experience there are good days and bad days, and it's not always obvious what's going on. So I think a check-up with a specialist probably won't hurt, as there are dysphoria and other non-helpful conditions less than full-on depression.

@schrödingcöder I definitely think there is an issue there. I am planning to resume therapy asap (I stopped during 3rd year of uni as my mental health got significantly better at that time). But even beyond that it could be that I need to take a month off to really put myself together and consider potential paths forward, maybe even talking to a career coach. Luckily my PhD offer does not expire until the end of summer and I have plenty savings from not doing anything outside of work for the last year.

Only you know your situation but it’s worth considering that entry level jobs are often just really boring. They don’t usually give the most interesting tasks to the new person for a variety of reasons, some valid, some not. One of the valid reasons is that you’re (the general you, not you specifically) still learning the ropes and are a much higher risk to the project so are given lower risk menial tasks. So unless you’re in a toxic or woefully incompetent company or department (which is possible), you may be describing the typical experience for an entry level dev.

If so unfortunately the best I can say is do what you can to find joy in the menial work, learn all you can, network, and take comfort in the knowledge that as you demonstrate the ability to do menial low risk tasks well you’ll gain more responsibility and with it more exciting tasks. That said I agree with others that $30K is waaaay too low a floor for a salary for an entry level dev. Waaaay too low. You should be looking for at least double that if not triple.

The US has higher paying salaries. I didn't major in pure math but statistics, but I still find all parts of it very interesting, especially the programming parts. The starting salary for a data scientist with a Masters degree is $100k.

To do for a living what you actually went to school for, probably would require a PHD. If you'd got your masters in engineering then any job on the planet not requiring a doctorate is basically yours for the taking. ... Zero experience and a PHD? Then there's no proof that you're worth what you think you are. A HS dropout with 10y exp? Gimme that guy; he shows up everyday, and doesn't complain that his life didn't turn out the way he paid a school to tell him it would.

Folowing the most upvoted comment: if you need a better job, probably asking at the workplace.Stackexange would yield better answers.

@bob It's probably £, not $.

Yeah you’re probably right. Wasn’t thinking of pounds. Ok I retract the part about salaries since I don’t have any idea of what’s a good salary in the UK.