I worked in finance for 14 years. If you think that AI is going to markedly decrease the accuracy of the Excel spreadsheets underpinning our financial system, then you've never seen those spreadsheets.
I once saw a formula that ended in "+15". Because that's what it took to get it to balance. It was like that for years.
And honestly I worked at one of the better banks, one of the ones that didn't actually need to take the TARP loans.