I agree with your overall point that Apple ought to be better about repairing old iPhones, but I would also caution you to wait a bit to see how reliable your iPhone X will actually be after that mall kiosk repair. I had an iPhone X screen replaced by a mall kiosk and it was awful. The screen kinda worked, but had lots of problems flickering and the touch screen seemed very unresponsive. The screen quality itself was also terrible. It wasn't OLED and had terrible color range and contrast.

All that is to say that while they did repair the phone enough to make it just barely usable, for less money than an Apple repair or a new phone purchase, but that's about it. If I had that same experience from Apple it would be totally unacceptable. I hope your iPhone X continues to work well for many more years, but I would be surprised!