In practice wouldn’t any fork mean that any and all transactions carried out in the response time are lost? Or would you somehow rebuild those honest transacti

In practice wouldn’t any fork mean that any and all transactions carried out in the response time are lost? Or would you somehow rebuild those honest transactions? (I assume you can’t because of the chain). It’s pretty worrying if a 51% attack could happen, any transactions happening at the same time could be reverted, especially because there is no dispute resolution or guarantee that the person you traded with will resend the funds.