Almost certainly this isn’t anything to do with scraping. Like with Reddit, those with a stake in Twitter stand to benefit from AI and, as far as I know, there’s no mass reposting (retweeting?) effort to something like Mastodon.
That would be trivial to block anyway, since it would be easy to identity the service accounts and source IP’s of the requests. No need to impact average users.
What’s more likely is he hasn’t paid the bill for his cloud infrastructure and no longer has the capacity to serve so many users.
IMO, that’s what you get when you fire half of your staff.