> well, luckily, that's not how money is stored, but instead, they're transaction based.

Not really. That's how the accounting works. It's the gold standard, and what we guarantee our customers, it's not universally how we store it though. Plenty of bank systems store just singular balances and infer that back into "transactions" in other systems to make the balance even out. Then the errors in those balances are manually corrected by looking at the sums.

IT systems only rarely match the legal frameworks they operate within.