I don't use 1Password (I've tried dashlane, lastpass, and bitwarden), so I'm curious what the actual implications of this are. I don't think I've ever looked at the name of my password vault. Obviously changes should be communicated with advance notice but it's odd that anyone cares. There just seems to be a lot of anger/aggression that feels either misdirected or overblown.
I did receive the email they claim to have sent and there was also a banner on top of 1Password for a few days prior to the change notifying you that it was happening and linking to the relevant Blog post.