I'm wanna thing there are a lot of better ways to avoid a black market, than creating more e-waste with disposable devices impossible to repair.
Do you seriously believe Apple is sending everyone new iPhones and not repairing them at all?
That would be a stupendously bad business decision.
Careful, if Louis Rossmann reads that you may give him a sudden case of apoplexy.
The only thing "fairly reasonable" about what Apple likes to charge is that you fairly reasonably may as well just buy a new phone.
Not a single time was the cost of repair even close to the cost of a new phone.
Doing it without the meagre compensation they give now would be deeply unethical, Tesla tried something like that recently when a story emerged that someone was quoted for full out of warranty battery replacement for a broken cooling hose fitting on their cars battery and they refused to give any core charge even though the battery itself was still fully functional (https://www.youtube.com/watch?v=n8-OkfCcRAo).
I'm more worried about someone stealing my phone (where the cost is the whole value of the device) than I am about breaking the phone (usually my fault) where the cost when repaired by Apple is fairly reasonable.