Earlier quoted context omitted.
OK it's true there are also more issues at play. Since you mention battery, that's a big one. When Apple cannot control which batteries get swapped into their devices, their brand is at risk due to fires caused by bad batteries. You can generalize this point to other components and quality in general. If people swap out third party parts, which some repair shops and end users will do to save money, the products end u…
This is really not a good argument. If I swap the parts myself, I either get the new parts from apple themselves (in which case it IS their fault if something goes wrong or they can blame it on me for wrongly assembling it; e.g. "You were holding it wrong") If I go to a shop or a friend to get my phone repaired and they replace parts, this would be different. If the device malfunctions I would obviously blame the guy…
But it is, and your counterpoints do not hold up.