[C4K3]

A reasonable solution would be to have a "Do you want to disassociate this phone from your iCloud account?" prompt as part of the factory reset.

[dawnerd]

I thought this was the case already?

[literalAardvark]

On the Samsung J5 2017 you need to delete the Google accounts before resetting.I haven't tested FRP on anything newer.

[SpikeDad]

It is. iOS prompts to remove the Find My setting (iCloud Lock) when you use the Erase everything prompt. Requires entering your Apple ID password.

[sneak]

This already happens.