Title is a little misleading (on purpose, I shoud say). I agree on what you said.

Moreover, I'm thinking about the onboarding of new users into a few years: onchain is already prohibitive for some users and use cases, sovraign L2 solutions are ok, but still an onchain settlement and transaction has to take place. L3 solutions are mostly custodial. Will a new user be forced to use bitcoin custodially in the future because no other means are available?

For some situations im third world countries it's allready the case..if I save 30 bucks a month I'm not willing to spend them on fees, am I?