If security was the primary concern, Apple would sell this as a separate model variant (manufactured in the USA) and charge a lot more for it.
Gays, minorities, journalists, dissidents, whistleblowers etc are all being targeted and jailed in many countries in the world. And in China it's entire swathes of the general public. And so much of this is directly attributable to lax privacy and security.
And I don't know believe that there is a huge market for cheaper repairs of Macs. Most people are still just going to local service providers who are authorised by Apple anyway. Otherwise getting hold of parts can be difficult.
If they weren't actively shitting on repair companies, I'd say there'd be more of a market.
You can get an iPhone screen repaired for peanuts. Apple quoted $190 to do it. Shop did it for $95.
Speakers replaced on a MacBook Pro? $45.
The issue is with allowing replacement of parts where you could do something that compromises security. Replacing someone's display assembly with one that disables the on light. Or swapping keyboard with one that has a key logger.
It has nothing to do with ensuring product turnover whatsoever.
Third party iPhone screen replacement is generally not worth it due to shoddy warranty by the shop and noticeably worse screen quality. Where it is worth it is when you are already out of warranty and trying to extend the life of your phone.
The SSD is probably closest, although Apple does have custom part #s with custom firmware.
With the exception of the SSD. The screen and speakers etc are the same as Apple uses.
See, it's all about pricing, not quality of the parts. Last iPhone I sent for repairs at work came back with an invoice of 340€ for a screen replacement. At work that's something we _have_ to do, we can't send the phones anywhere we want. But if it was a personal phone, if I'm out of warranty and I'm going to be billed 1/3 of the cost of the phone for a new screen, or 100€ for a refubrished part somewhere else, it would be an easy decission.
Now, if that aftermarket repair was out of the question, you start wondering if it's worth to spend 1100€ for the more basic version of the phone, or you just spend 200€ on a Xiaomi and if it breaks you still can buy 4 phones more if they break. Or maybe you buy an iPhone still, but then when it breaks you just throw it away and buy an Android phone. Maybe the first time it won't happen, but after you have spent 1500€ on a phone and something else breaks(battery? lightning connector maybe?) it comes to a point where you stop throwing money into the hole.
On the laptop side, I get what Apple is doing. It has their new flashy T2 chip with integrated Touch ID and they're trying to do the same thing they did with the iPhones and nobody is going to stop them (well, maybe in EU they force them to allow the sale of Apple Diagnostic software to 3rd parties or fine them)
They're trying to convert their computers into big iPhones and treating everyone like a child that has to be taken by the hand and told him what to do all the time. And that is my problem with Apple. I'm not worried of somebody putting a backdoor in my laptop (and if they wanted to backdoor my laptop a year ago they only had to type 'root' [enter] [enter], no need to open the case), I'm not that interesting to anybody or any agency, but I don't like to be treated like I have no rights on the things I buy, and I don't need permission from anybody to do whatever I want with whatever I paid with my money.