I'd be fine with doing verification of parts like that if and only if it doesn't lead to nonsense such as scary popups warning of damage or reduced functionalit

I'd be fine with doing verification of parts like that if and only if it doesn't lead to nonsense such as scary popups warning of damage or reduced functionality or what have you. Obviously this also implies that to create a replacement part you don't need to ask the original manufacturer for permission. A "third party signing" key should be publicly available.