Maybe you can talk about which parts are not available and/or are unreasonably expensive.

Because looking at the repair site it looks pretty comprehensive and you can even hire everything you need for $49 a week.

I’m sure Rossman has legitimate complaints that he can’t order thunderbolt controllers or whatever in bulk from Apple to conduct complex main board repairs in his repair shop, but the fact is that any repair that Apple themselves will perform at an Apple Store or service centre is performable at home with official Apple parts often with significant discounts over getting it done by Apple.

I recently replaced an iPhone 12 Pro Max battery myself at home for £44 rather than the £85 Apple charges to do it for me. All I had to do was send them my old battery. No NDAs or sketchy agreements.