Far more than we have fingers and toes to count them on. :rolleyes:

A couple notes:

1) A bank account breach for a personal/consumer account is protected - your actual out of pocket loss should have been zero/minimal. Protections for cryptocurrency = zero.
2) A bitcoin transaction actually costs more like $3000 - that's how much bitcoin is being "fiat created" to compensate the miners. The $20-$70 is closer to what the electricity cost per transaction is. Interestingly, the crypto supply has increased roughly 15% in the past year due to mining - which is a far greater increase, on an annualized basis, than almost any fiat currency.

1) Your bank accounts are not protected from the IRS and/or other Governmental Agencies. They can freeze and seize your assets on the flip of a dime.

2) Most cryptos will be out of biz in the future. You're better off looking at the pioneers which will still be around in 5 years. How much did BTC's supply increase in 2018?

I would trust more any mileage program that is related to blockchain.

For example United Miles but then actually not miles but actually to be coins.

Blockchain is only a technology. It is not related to currency except in certain specific implementations like its most famous implementation, Bitcoin. But in that case it's only the implementation of blockchain, not blockchain itself, which makes it be about coins. So ti would still be miles, not coins, if United Mileage Plus changed nothing other than the technology to blockchain.