From the official announcement

Can I buy an account on a device that has no Play Services?

Not yet. We have plans to add more payment methods, but currently only offer Play Store in-app payments, which requires Play Services.

Ok so given how long it took them to allow an alternative to phone numbers, it will probably be at least 5 years before you can pay using a de-googled phone. I really don't understand what's so hard for them to accept crypto, they already do for donations. Smells like government involvement.