How much does the insurance cost? Was it hard to find someone wiling to insure that? Finally, you pay 0.2% but Ally pays 1% yet you say your rates are as good.
On the interest rate side, the 0.20% is the base rate. If you win no prizes, you get that. Prizes comprise the bulk of the value from Yotta. Your total return is prizes + the base rate.
On the insurance side, there are specialty insurance companies that do this kind of thing, similar to hole in one prizes or half court shot prizes at sporting events.
We pay them a mark-up on expected value. Since the risk they're taking is purely mathematical random chance, it's pretty much the best type of insurance for someone to underwrite. There is no uncertainty about what the risk is to them, unlike most other insurance where people are using actuaries to estimate what the risk is, but it's not actually known for sure.