This makes no sense. I've done numerous screen replacements and button replacements for friends/ family. It's stupid easy to do. The issue isn't that the replacement part doesn't work, you can use an OEM screen/button and you will get the same error unless APPLE Re-validates the Touch ID to the phone. In the past (iphone 5s) Apple just disabled the touchID, now they decided to brick the whole phone... The replacement parts work just fine and don't cause any issues, Apple just wants you to come to them. Just like jailbreaking your phone isn't illegal but they sure tried to stop you from doing it.
It makes sense if someone hacked an iPhone by replacing the Touch ID sensor and exploiting a security hole in iOS. If they then reported the hack to Apple, then Apple would do their best to close the hole in newer versions of iOS. They probably wouldn't issue a press release explaining how to hack older iOS versions to get at people's personal data. They would just fix the hole in a later release.
Your past experience replacing your friends and family probably put their iPhones at risk, but if you're lucky, the exploit was not well enough known for anyone to take advantage of your incomplete repair jobs.
I agree that Apple wants you to come to them for repairs. It's not just about money. They want to control the kind of hardware their software is running on, so they can provide a consistent level of quality. It's been their strategy from the start. You'd think the company that ran the 1984 Big Brother ad would follow up by licensing the Macintosh operating system to run on any hardware you wanted. That would be true freedom, right? Anything less is everything Jobs and Wozniak were claiming to be against, right?
I realize that there is no way to convince anyone who feels oppressed by Apple's attempt to control their ecosystem. And certainly no way to silence those who are outside that ecosystem but like to take potshots at it.
All I can say is that this is nothing new, and the end result is a system that is a joy to use for most of the people using it. Complaints about "walled gardens", non replaceable batteries, and soldered RAM were around BEFORE Apple's impressive rise.
I've been the "victim" of an unauthorized repair that bricked my iPhone 5. I dropped it and shattered the screen, so I took it to a place in the mall that replaced the screen for a lot less than it would have cost at the Apple Store a few doors down. It was a little thicker than the OEM screen, but otherwise worked fine. Then later, Apple issued a recall for iPhone 5's that were experiencing battery problems. They would replace the battery for free if your iPhone was in a certain range of serial numbers. I took mine in, but the tech told me he couldn't guarantee the non-Apple screen would survive the repair. I had to decide whether I wanted to fix the battery and risk the screen, or keep the screen but keep the battery life issues. I said to go ahead. (I had already ordered my iPhone 6 and was waiting for it to be delivered.)
Sure enough, the phone came back with a crack across the middle, and it not only wouldn't respond correctly to touch input, but registered touch input randomly when no one was touching it. I couldn't use it to make phone calls. I couldn't answer calls, even with a headset because the random touches would hang up with no warning. I couldn't sync it, or back it up, or even turn it off (I couldn't swipe to complete the shut down). I had to let the battery run down, and then wait a week for the arrival of my iPhone 6.
