I somewhat agree: "trust somebody" can be quite efficient. But it's prone to bad incentives (undeclared fractional reserve) which can drive out good actors (who are not as profitable) *then* collapse. I know nostr:nprofile1qqs9pk20ctv9srrg9vr354p03v0rrgsqkpggh2u45va77zz4mu5p6ccpz4mhxue69uhhyetvv9ujuerpd46hxtnfduhsz9thwden5te0dehhxarj9ehhsarj9ejx2a30qythwumn8ghj7un9d3shjtnswf5k6ctv9ehx2ap09krt7g has thought about this a fair bit, and has a rotating ecash solution which may address it well enough?