yeah except now you will exchange your fiat into crypto with some shady guy instead of a somewhat-trustable big entity with reputation.
Even Paypal and Cashapp are trusted crypto exchanges now. The crypto you receive there can be withdrawn and access the entire crypto economy.
I mean it certainly does the job but I'd die from stress if I would risk releasing a bug that could wipe hundreds of millions of users' money. I respect people who are good enough at Solidity to be reasonably confident.