My entire company and tg-part of a friend circle uses them when needed. E.g. to discuss issues that contain private/financial details or something personal that is undesirable to leak to "third parties who ruin parties". Otoh, I wouldn't mind if my mile-long chat with IT buddy went entirely public, because we mostly discuss Web-tech, BTC and other sick jokes there.

Personally I'd never bother to start a secret chat with a person that I don't trust enough anyway. Neither do I trust an e2e messenger that my country didn't even bother to "pucker" legally.

>users (wrongly) perceive it to be magically more secure

This is claimed often, but I'm yet to see these users. Do they really believe that, is it just tg opponent's agenda that became popular, or both?