So is there a problem with Apple or no?

I'd absolutely never trust Google to manage passwords/passkeys for me, with their habit of irrevocably auto-banning accounts. Apple seems... better? But that's today. That could change, and then you'd be screwed.

You're not limited to a single passkey by the spec or 99% of sites that support them. The limit is arbitrary and typically when a limit exists it's no fewer than 3 (very rarely 1, but I've only seen that once that I can recall).

I generally add three, one for Bitwarden (my actual password manager), and then the OS passkey store (Android/Chrome password manager or iOS/Apple Passwords depending on the device).

I'm not qualified to say yes or no; but I will say that Apple's tends to make design decisions that try to empower the user as much as they can while still being easy to use, and have more or less maintained that position.where as Google, on the other hand, started as "open" and "you can do it all on our platform" to "we're taking away your control and choice little by little, in order to 'protect' you". Oh, and you hear more about Google perma-banning your account for no clear reasons, than Apple...