Is "Proof of Reserves" really meaningful? Because to me it looks like exchanges are just putting off-chain data on the blockchain, obfuscating the mechanism of how it works with buzzwords and hoping the marketing aspect of it is valuable.

A = L + E, proof of reserves is only *some* of A. No exchange will show you L (except Coinbase, b/c they’re a public company)

download meeeee @ blobs.lol;
win up to $75 every week!!!

That seems pretty useless then, no? If the intention is to to be transparent and show everyone that they're not the next bankrupt crypto company  - it seems FTX could've implemented "Proof of Reserves" with no dilemmas.