Around minute 40 there is a great discussion of “auditability vs privacy” tradeoffs: https://fountain.fm/episode/1FaKA0B4a6wSn7fITcOn
...... something I hadn't fully conceptualized, but when it's explained like this, makes a lot of sense. Basically the L1 can't be fully private if you want anyone with limited storage and compute power to be able to audit it.
Privacy is a good job for L2, which is yet another great reason we should resist bad actors trying to centralize L2s like Lightning.