The move to the new PDS v2 hosts seems to have been transparent and problem-free for almost everyone. But anyone having trouble should check that their adblocker/plugins are not preventing access to the new DNS names. One (imperfect) method of checking is the debug page: bsky-debug.app

Please consider hosting mushroom cloud on the same DNS name as the old server.

Not a real option. There needs to be lots PDS hosts in different regions ultimately. This is just the first set.

I mean subdomains of the same domain. a.bsky.social b.bsky.social And so on. That tld is already whitelisted at most places.

Yeah, point taken, but there would probably still be cases where the entire domain hasn't been trusted. It's common to have CDNs and other things like this on alternative domains for various reasons. And fortunately, this is the last domain to worry about for the foreseeable future.