100% agree. They cannot reverse the dispute. I already lost the money. I understand.

But Stripe is exactly in a position to at least use the evidence I provided (in this case, the evidence included the customer clearly admitting to friendly fraud), and feed it into their fraud-prevention system in some way. This way, lots of signals can help protect merchants from friendly fraudsters. So yes, I see it as a pretty small and legit ask from Stripe.