“Passwords with landlords” because you do not control them or own them. They live in encrypted storage you don’t have the keys for, or in cloud storage that you are borrowing from a private company.
Have you read the nightmare stories about people being suddenly locked out of their Google and Apple accounts with no notice or provocation? Imagine that but with your passwords; now it’s not just your Apple account, it’s all of the accounts you trusted them with.
Just use a password manager that generates and stores sufficiently long passwords for you, along with TOTP or hardware keys. That gets you the best security without handing your life over to large corporations.
You can, but you still depend on the site to let you use that option instead of a major provider.
When passkeys were first introduced they were not transferrable or even useable outside of the big providers, because the platforms wanted that sweet sweet lock-in. I wrote off passkeys when I realized this. Perhaps things have changed more recently.