A card subscription works because the merchant initiates the charge. Crypto has no equivalent; the customer initiates every payment, always. That single difference breaks the entire recurring model and I have not found anyone writing about it honestly.
My product is billed monthly. Moving it to crypto means that every month, every customer has to remember to do something. I already know what that does to a renewal rate and it is not a small number.
So what are people running in practice? I am less interested in which gateway has "recurring" in its feature list than in what the actual retention looks like once the customer has to press the button.