I was specifically talking about the Mac.
> System Settings > Lock Screen > Require Password after screen saver begins, can be set to Never if you do not want to be required to enter a passcode.
This will be greyed out if on your Mac the iPhone Mirroring app is set to Automatically Authenticate. This is in the Settings of the iPhone Mirroring menu when the app is open. You said that you get a message that says the app is not compatible with your Mac, so I was asking if you are still able to access the Settings even when that message is on your screen.
The iPhone Mirroring app is only compatible with Macs that have the T2 chips and the only model I know of that will accept Sequoia and does not have a T2 chip is the 2019 iMac, which may be the one you have. I don't have that model, so I can't confirm if you are able to access the Settings of the iPhone Mirroring app.