> I've been hearing about bitcoin for 15+ years and I don't think I've ever walked into a shop where they accepted it.

I didn't say bitcoin. I said blockchains that use USDC.

> So, approximately six 0s of uptime for my use case?

No-one cares if 1 person (out of 8 billion and trillions of bots) won't use it. It exists and Shopify and Stripe have crypto payments with USDC which is useful for both humans and agents.

[0] https://stripe.com/gb/use-cases/crypto