I think the article conflates different scenarios: I don't think many people expect that a web service gives detailed technical error messages to external users

I think the article conflates different scenarios: I don't think many people expect that a web service gives detailed technical error messages to external users who might be attackers. But the really annoying appearances of the "oopsie woopsie" messages are if they happen on a local system, where there is no other party - neither a potential attacker, nor any "administrator" who should be trusted instead of the user. So if there is no one else except the user, who should fix the error?