Passkeys were hot last year, don’t seem to be catching on, here’s one view of why that is. Dark and sobering but convincing: https://fy.blackhats.net.au/blog/2024-04-26-passkeys-a-shattered-dream/
Passkeys: A Shattered Dream

Firstyear's blog

@timbray For me the biggest problem with passkeys is they aren't fully portable across platforms. I use Debian and Alpine Linux, iOS, Android, and when I have no other choice, Windows. If I create a passkey on one platform it doesn't work on the others. Also there's no system level passkey support in either Linux variant I use and Windows' passkey implementation has been both convoluted and unreliable for me.
@timbray I do like that password managers are starting to support passkeys. I've started using Bitwarden to store passkeys. I store them once and they are available in the Bitwarden browser extension in my Firefox and Blink based browsers on Windows, Linux and presumably MacOS too. iOS and Android support are "coming soon" to Bitwarden. KeypassXC recently added passkey support too but it's Linux only, unfortunately.
@yeswap
I’m sure passkey support will come in the following months for the missing platforms. It will also come at the system-level on Linux. I think we just need a bit more patience on this!
@timbray