Also for old people, its impossible to fall for a phishing page using Passkeys. Unlike auth codes where you can type the code in to a fake login page.
Unfortunately that breaks down when someone doesn't set multiple keys as backup and gets locked out. Then you're right back to password/backup code or some kind of recovery to email or phone. Chances are people just store their backup codes as plain text too. They also break down across desktop/mobile, e.g. register on desktop then try to log in on mobile. Not everyone has a good sync solution here, especially the non technical.
Honestly all the solutions have trade offs in UX/security/privacy and dependency on third party services. The best solution is going to be highly dependent on the business.
The UX issues of Passkeys can and are being fixed. The issues with passwords are unfixable.
I don't see any solutions to the recovery problem that doesn't introduce another login mechanism. But as a primary method the UX is pretty good for the technically literate.
For an old person who basically just uses an iphone and ipad, you can't screw it up and you can't be scammed.