I finally looked at this safe harbor IRS thing.

I'll bet that it's impossible to enforce because what they're asking for is impossible to report, so it's a tactic to harrass a bunch of Bitcoin holders.

I've always done my taxes under the assumption that Bitcoin is fungible, so all BTCUSD transactions from any exchange I used that year just get batched together into a single report, with sells matched with buys from any source because I could buy on one platform and sell on another years later. I'm just going to do the same thing for 2024.

As far as I've always been concerned, the IRS has no business beyond the point of exchange with USD. I don't even think they have any business knowing which exchanges I used.