Small issue on your argument against ecash. The nym thing is only today bc of lack of regulatory clarity. One family/neighborhood member running an ecash mint as a nym, but the members actually know the underlying person is a good model bc you can always go to their house and attack them if they rug pull, and considering a mint should never have more than a single bitcoin in it, I think that's fine.

that's fine but the point is you can do exactly the same thing on L1 with bigger blocks. just instead of running an ecash mint you run a node. the main difference being you actually have basic L1 assurances instead of a Rube Goldberg machine you have to maintain built on top of L1.

My best hope for Bitcoin banks that don't give up privacy or rug risk so far is Fedimint. I don't know if they've quite neutralized rug risk but they seem like they may be getting there with some creative methods of blinded federation.