The one time I brought my laptop to an Apple Store for a serious repair, they asked for the password to my primary account. I told them to just wipe the drive if they needed access.
Wouldn't work with iPads. If you have connected your Apple ID with the device and forget your password, you cannot even reset the device. Not sure on phones, but pretty sure it works in a similar way. Macs are probably different though. A "If they could, they would"-situation probably.
Newer Macs with T2 chips and Activation Lock enabled are similar. In either the case of T2 Macs or iOS devices I'd be happy to just reset the device myself rather than giving credentials. I was surprised that they asked at all - in my mind, asking someone for a password is verboten.