Self-custodial wallets with decent UX require other tech - on-chain Bitcoin for regular transactions is unusably horrible. If you want Ark, Spark, Lightning, Rollups, or literally any of the things that make Bitcoin usable, you need someone (or many someones) to run nodes, sequencers, or many other things. Ensuring those things aren't made illegal in the US is important, no matter how much we pretend it isn't. If only so that developers can build them in the US, and people can run them outside the US later.

This is inaccurate. The California bill actually ensures that the state wont sell your coins if you haven't logged into your custodial account in three years.