Onionland people had plenty of warning though. My old v2 Onion bookmarks are all discarded. The new V3 addresses are a good indicator of which .onion operators are serious and want to stay online no matter what.
I consider myself pretty active on tor. I've hosted a number of services for a decade. While I heard about the new Tor v3 services a long time ago I didn't hear about Tor v2 support being completely removed until April 2021. It was quite a shock.