Funnily, the way I used to check Keybase profiles is to check Twitter because a blue checkmark there was usually a good indication of them being "the famous person" but thanks to Twitter Blue that feature is no longer usable.
I understand Keybase allows you to link up a bunch of accounts, but it doesn't prevent you from making all of those accounts say you are the CEO/CTO of some company unfortunately.
> but it doesn't prevent you from making all of those accounts say you are the CEO/CTO of some company unfortunately
At least a GitHub profile link can usually be used to validate that this account actually has write access to a GitHub organization, so you can somewhat see it's the right person. Requires them to have pushed any public commits to within that organization though.