@user21820 I have downvoted that answer. But unless we get sufficient downvotes and a few delete votes, I don't think applying unilateral deletion solely on basis of mathematical incorrectness is a good idea.
I hope active members in this room will take care of the downvotes on the bogus answer you have linked
Ok thanks! ^ @Ѕааԁ @RRL @TheSimpliFire @MartinR @JoséCarlosSantos @XanderHenderson: Please help downvote these two bogus answers here and here, thank you!
The second one has now gotten 4 downvotes excluding mine since I posted it here 16 hours ago, and the author's comment shows that he doesn't even know what's wrong despite Lucian's comment from 7 years ago. So is that enough for you to delete it too?
@user21820 I have downvoted the first one. But I don't see what's wrong with the second one. All that is missing is a detail: if $a_n>b_n$ for each $n$, then $\sum_{n=1}^\infty a_n>\sum_{n=1}^\infty b_n$. Besides, it looks equal to this answer.
@JoséCarlosSantos Uhh it's obviously wrong, and I also downvoted that other answer for the same reason but the saving grace is that ShreevatsaR posted a comment to fix it. But the post I linked was not only wrong but was posted > 2 years later, so it is completely worthless.
It's not about whether one can fix a wrong argument by adding an entire extra argument or not. It's what the original post conveys to the audience, most of whom are beginners in real analysis.
So when I say "wrong" I do not mean that the conclusion is wrong, but that it is not a correct justification due to missing essential ingredients.
No context question with three answers: math.stackexchange.com/q/4357662/42969. I suggest deletion (one more DV needed) since OP did not response after 16 hours.