Actual money from sender to receiver was covered in my original post - receiving SPL USDC is receiving actual money. But see below for what to do the fantasy world in which is it not.

If you deposit to FTX via ACH that costs $0. If you send yourself SPL USDC from FTX that costs $0. If you send someone else SPL USDC that costs less than half a penny. If that person sends SPL USDC to FTX that costs less than half a penny. If that person withdraws USD from FTX via wire transfer that costs $0. The sum of these figures is less than a penny. As I've written upthread, this might not work out exactly the same way depending on your choice of exchange, country, and bank.