this deleted answer shows that many users do respect the EoQS when they are notified of it.
Also I have seen a few suspensions for low quality contributions which implies the EoQS being enforced (at least I guess so). We can hope for some perceptible change in behavior of users soon.
@supinf No, I don't think you were in the wrong for two reasons: (1) I don't think there are "site standards" regarding voting - voting is inherently opinion-based (just don't do anything silly like downvote all their other answers). (2) When down-voting an answer, the condition is "This answer is not useful", and an answer going against the EoQS is not useful for that reason.
@alex.jordan Any user with sufficient reputation my downvote any post they please, for whatever reason they like, just so long as the downvoting is directed towards the content and not the user. The page to which you linked is a set of guidelines, and is not exhaustive. — Xander Henderson ♦3 mins ago
@supinf I think their comment that "You may not know that the "standards for the site" have gone back and forth on this issue a number of times over that time" is interesting, but needs backed up. I have been here for basically as long as that user (~600 users joined between us), and after about 2012/2013 I think the standards have been pretty consistent.
Maybe expectations were different from reality for a while, but that question falls below those expectations. But we're both working from memory, which is why I think it is interesting.
@supinf Thanks, yes, that's how I'd like it to work. Besides, I'd flagged : turns out all (with the exception of inactive users) users above , say, 60K have been EoQSed. So we are in great shape regarding flagging these users directly. However, regarding the user who did reply : I'm happy that you EoQSed them, because that's the first time I'm seeing this.
@supinf Another small thing : keep track of users who you've already flagged, and let us know via the chatroom and indications who you've flagged by putting the relevant post up : not in the interest of targeting, BUT (1) for flagging so that they aren't EoQSed on multiple occasions and (2) to follow up on rude responses. The work is faster, more efficient, robust and ultimately saves conversation fatigue.