Long time ago, Darth once told me that we should use the power of custodial to attract more people to the system, get them to know and them BAM! you catch them because, going down in the rabbit hole, that's gonna happen.

This is just me but I never met (until today) a bitcoiner (maxi or not) that started with custodial and kept it with something related to that. Most people that take their economy by their own hands, ends with HW (Trezor, Ledger, etc) or self-custodial wallets.

So, IDK..mainstream? maybe not but mainstream for graduate your bitcoin class (aka take the orange pill)? It's something that I had in my head for a long time.