Yeah, crypto IRAs may very well exist, it's just that the brokerage my IRA is at doesn't support them. My non-retirement brokerage supports cryptos but doesn't have IRAs. Well, they sort of do; I can buy a range of cryptos but it's only a bet, I can't actually withdraw them or do anything with them, which seems half-assed to me.
Maybe someone will come along and recommend something better to me.