This might not be possible, @appadeia has a draft merge request to fix this for the polkit agent, but... it might be stuck for a long time: https://invent.kde.org/plasma/polkit-kde-agent-1/-/merge_requests/32

No I understand that, but:
Previously polkit supported fingerprint autentication. Only failing that, you would be able to login via password.
Now the PAM config was split into 3 files, and what previously was the merged fingerprint+password config /etc/pam.d/kde is now only for password auth.
If polkit is not updated and keeps using that config file, it will lose the ability to authenticate via fingerprint entirely, nevermind simultaneously.

d_ed suggested that it's possible to ship the previous merged config file for polkit only, retaining the ability to do fingerprint in polkit while using the new cool kscreenlocker features.

Nevermind, i understand now.

Polkit doesn't use /etc/pam.d/kde, but /etc/pam.d/polkit-1, so is not regressed nor affected at all by the change.