“Very good UX” doesn’t really describe interacting with public cryptocurency networks for me between the security concerns, transaction times, and obscure address names. Is there a particular use case that you have in mind where that’s an improvement on the status quo from a UX perspective?

Are you including signing up for a credit card or bank, making sure you don't have inactivity fees in your checking account, paying your bills on a monthly basis and incurring late fees and credit score dings if you don't?

Yup, all-in the sign-up is roughly the same, the bills are pretty easy to keep paid, and fees are far less inconvenient than the possibility of losing control over a financially-significant private key.

IBAN is not much more meaningful than a random string. International transactions usually take a day or more.

I don't think that aspect of centralized banking infrastructure has "very good UX" either. I could imagine something like PGP where the key management around hardware wallets and an interface like https://etherscan.io/ was serious UX improvement, but wasn't broadly disseminated knowledge yet.