“Not your keys, not your crypto” is one of the most out of touch axioms in the crypto space (and that’s really saying something).

See: the vast majority of the population (even within crypto) that can’t figure out how to setup a wallet in the first place. Then, if you get that far, you can join the hordes of people that lose access to it, dig through garbage dumps for a laptop, have malware that inspects the clipboard and replaces addresses, make a wrong click in Metamask and get cleaned out, etc, etc, etc.