PoR ratio everyone screenshots doesn't mean what people think it means

Quick context for anyone who forgot: FTX collapse in 2022 is why PoR became a thing at all. turns out there was no way for users to independently check if their balances were actually backed - investigators found something like $8b in customer deposits had been quietly funneled to alameda. after that every major exchange scrambled to prove they weren't doing the same thing

traditional Proof of Reserves basically consists of two halves. Proof of Assets (cryptographic signatures showing the exchange controls the onchain wallets it claims) and Proof of liabilities (aggregating what it owes users, usually via merkle trees). some exchanges go further with zk-SNARKs/zk-STARKs so you can verify your own balance was counted in the total without seeing anyone else's balance.

but here's the gap that never gets mentioned when PoR comes up - it's a snapshot. one moment in time. it doesn't prove the exchange didn't shuffle assets in and out of those wallets right before the snapshot to pass the check (this has actually happened before with smaller exchanges). it says nothing about fiat holdings or offchain liabilities. and it definitely doesn't tell you what happens to those "proven" reserves the day after the snapshot whether they sitting idle, or are they out in lending/staking/bridges picking up risk nobody's disclosing

so PoR is necessary but clearly not sufficient on its own. The block`s research frames it as one layer in a bigger trust stack, asset segregation (so customer funds can't get commingled with the exchange's own, which is literally the exact mechanism that turned FTX's losses into customer losses), regulatory oversight, and actual insolvency protections like insurance funds or defined creditor treatment in bankruptcy. And what do u think about it?