Great points.

I might add:

I strongly suspect that a much bigger fraction of the free volunteer labor moved here, than anyone has realized.

Zuck and Spez know how fucked they are, but they're motivated to downplay the damage to their platforms.

There's an unvirtuous cycle where their platforms have under-resourced moderation, which has allowed bot proliferation, which has made unpaid moderation work a shittier job, which causes moderators to leave, which allows more bot proliferation.

Folks here seem to be saying our moderation tools are objectively poor, but are getting better with each release. So it's the bot spammers whose life gets harder, over time, here.