@AlexanderGruber Indeed, that's why I put it up for discussion here. Anyway my 'argument' is that there are too many Collatz cranks that it becomes or negligible worth to have a refutation for each one of them. Taking your 'argument' to the logical end would mean that we should put up with a question for each one of them, which as per amWhy's remark is surely not what we want.

For me, anything that can be identified as crankery based on the FAQ should be removed from Math SE, but genuine questions that do not appear to obviously fall into the crankery bucket as per that FAQ do deserve to be kept, precisely because it is harder for people to figure out what they are.

@AlexanderGruber As for popularization, many pieces of crankery only came to my knowledge via Math SE. And I am not even actively looking for it. So in some sense Math SE is popularizing them. The worst part is that each of us waste a certain amount of time reading such junk just to find out that it is junk, and then spend another bit of time wondering how it got so many upvotes. =P

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My opinion about posts like "has Collatz been solved ?" : Such posts are off-topic and the popularity of such questions ("upvoted to heaven") does not mean that they are entertaining or interesting. Many people only upvote becuase they notice a surprising message of a "proof" that is in the vast majority of cases "not even wrong". If we want to improve this site, we must "clean" it from those posts.

Nonsense sells , we cannot change this , but we should at least not even support it.

@XanderHenderson And now it has been reopened... :\

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@XanderHenderson I tried to help out with a delete vote. My actions are less effective than yours.

D1, D2, D3.

D4, D5, D6.

D7, D8, D9.

D10, D11, D12.

@XanderHenderson Why can't one of you moderators close it?

C4, C5, C6.

C7, C8, C9.

C10, C11, C12.

@user21820 I did close it. I was reopened.

Unilaterally overruling the votes of those that voted to overrule me seems like a rather authoritarian move.

@XanderHenderson Oh I see; I didn't notice that, sorry.

@XanderHenderson At any rate, there are far worse questions to delete. The one you point out should be closed, and I did vote to close. But taking time to advocate for its deletion, when there are sooooooooooo many more questions far lower in quality that you could advocate for deletion, is likely not a good use of your time, or ours.

How did this question get five upvotes? Please vote to close, later delete.