Oddbean new post about login | logout We still have this IMO, like sometimes I see arbitrary kinds when my signer asks me to sign something. Fortunately, the most popular kinds are now recognised and labelled but it doesn't change that there are still arbitrary kinds.
yep, but the number creates the user pressure on the dev to label it in a NIP otherwise users don't know what those are. Usually pro users are quite vocal and can be pretty annoying about these things. Useless kinds will remain undocumented, but they are useless, so who cares.