> if a writer enters an infinite loop while writing the shared data, that will stop progress in any other algorithm

No, it won't, not in a wait-free algorithm. For lock-free algorithms, yes, it's a matter of scheduling and stochastics.

But this is not the case for seqlocks. You don't need an infinite loop, you don't need to keep writing. Just stop the thread after it set the seqlock value to odd ("being modified"). Because it's not lock-free.

(I do agree that a lot of this is overblown and ill-applied; "lock-free" just sounds good and it's sufficiently available that people reach for it and end up overusing it. However, there are cases where it matters and is absolutely appropriate, and it also matters that we are able to have a conversation about these situations and conditions and use the terminology in a consistent manner.)

> using a lock for writers and using the method from TFA for readers

Case in point, I'm confused what you mean there, what do you mean with "method from TFA"? I don't see how anything in the article combines with a lock for writers.