Not only do you have to pay to deposit, you have to store it, count it, secure it and transport it.
It's the same problem all cryptocurrency projects face. They allowed Bitcoin because Bitcoin is basically useless for payments, it's too slow and fees are way too expensive. Though Ethereum recently slipping through the cracks may disrupt the payments industry in a big way. Coinbase and Circle are already working on bringing direct stablecoin payment options to customers/merchants with USDC and other tokens afaik. Which would also be more decentralized than Facebook's Diem. Not sure how many people would trust corporate money, an open public ledger is preferable of course.
https://www.ft.com/content/a88fb591-72d5-4b6b-bb5d-223adfb89...
https://www.dw.com/en/facebook-backed-cryptocurrency-sold-am...
Or authorities "allowed" Bitcoin because, given its lack of head to cut off, they had no choice.
Contrast with Ethereum's demonstrable central authority over its blockchain: When the developers were robbed of their coin by a hacker, they "reorganized" the Ethereum blockchain to undo the transactions associated with the theft.[0]
I regard Ethereum less as "slipping through the cracks" and more as a poison suppository greased and inserted by the powers that be.
[0] https://en.wikipedia.org/wiki/Ethereum_Classic#The_DAO_bailo...
I don't see why they should get to shave a slice off of every transaction. It takes relatively little upkeep and they rake in huge profits.
The fees nudge businesses to use cash (well, to avoid tax too, sometimes.) or set a minimum transaction amount, which can mean fewer customers through the door.
I think a new, public infrastructure competitor could be healthy for economies worldwide.