I'm not saying those account should dox themselves or whatever. There are plenty of official accounts on Bitcointalk (from exchanges, physical bitcoin creators, artist, coin developers etc.). Verifying could be as easy as sending a special tweet (or DM) from their official Twitter account. It might even help combat scammers since there have been plenty DMs sent by imposter accounts.
How's Twitter accounts' security wrt to social engineering attacks? In case of twitter even their CEO has had his account hacked.
Plenty of users here on bitcointalk lose access to their accounts, but that's usually (always?) the result of their poor security practices.
Great point, there could be other ways to verify (without doxing). A huge downside would be that 'verified' Bitcointalk account can be sold/used in scam attempts ( making me reconsider my suggestion).