Was this discussed somewhere? I'm not aware of another wiki that takes such a punitive approach - while GlobalUserPages is a thing yes, it's fairly common for some to still want to create their own local pages.
Topic on User talk:P858snake
Yes, It was discussed with numerous other admins on IRC, If a user really wants a local user page they can ask a admin to create the page and then they can edit as desired, There has only been 1 or 2 requests for it since 2022.
Is there a log somewhere where I can look at this discussion?
This strikes as quite a wrong move though - it's kind of established practice that we allow users to create a local userpage if they want (and in fact, many do have their own userpages on other WMF wikis). I don't see why MediaWiki should be any different - having to ask admins sounds like a very strange thing to me. I thought it was a spam problem that led you to impose this move, which is why I suggested allowing people with some global history to create their page here.
(Coming from a request at Project:Village pump)
First off, these sorts of discussions should be held on-wiki rather than on IRC for transparency reasons. Second, I agree entirely with Leaderboard on the merits here - the reason we have an abuse filter here at all is to prevent spamming, and the rest is simply your opinion on how to manage the wiki which other people, including myself, do not share.