Is it even a good idea to use physical security keys as passkeys in the first place? Passkeys are meant to be a password _replacement_, and for that you probably want the 2-factor properties afforded by phones or desktops which usually require "something you know" or "something you are" to unlock in addition to the "something you have" afforded by physically possessing them.
IMO physical security keys are better left as second-factor authentication, to be used _in addition_ to passkeys in certain high-security contexts; particularly where resistance to cloning is a critical feature. Resident keys aren't necessary for that use case since by the time you get to the second factor step you already know the account you're trying to log into.
Further, the autocomplete functionality afforded by resident keys is important for the UX of passkeys in my opinion. I don't think it makes sense to sacrifice that in order to to retain backwards compatibility with a small number of keys that only security nerds use. (Though if there were a way to maintain that UX without using resident keys I'd be cool with that.)
IMO physical security keys are better left as second-factor authentication, to be used _in addition_ to passkeys in certain high-security contexts; particularly where resistance to cloning is a critical feature. Resident keys aren't necessary for that use case since by the time you get to the second factor step you already know the account you're trying to log into.
Further, the autocomplete functionality afforded by resident keys is important for the UX of passkeys in my opinion. I don't think it makes sense to sacrifice that in order to to retain backwards compatibility with a small number of keys that only security nerds use. (Though if there were a way to maintain that UX without using resident keys I'd be cool with that.)