Passkeys are password replacements that can't be breached/leaked/etc... I don't think they are necessarily supposed to replace 2-factor, however it's probably more secure than some of the weaker forms of 2-factor auth.

Given that in order to access your password manager's vault often requires 2-factor (or should at least) it's a level of security that I am comfortable with.

I take it a step further and host the password manager vault within my home network. My home network does not expose anything publicly except a WireGuard port, it's completely locked down. I have to VPN in to access the vault.