Start with https://www.google.com/search?q=google+banned+all+apple+repair+ads and there it is. It appears to be mostly about Apple products and when two juggernauts, dare I write collude even if openly, we all lose.
Apple's repair system is OK when your device is under AppleCare but beyond that we see the repair price climb to levels where they essentially tell you to buy a new on.
I've had no qualms about many third party repair companies but Apple seems to have declared war.