One-off custom cars are a different thing same how there are YouTubers putting headphone jacks in their iPhones or upgrading the soldered VRAM of their Nvidia graphics cards.

Is this a regional thing? In Germany changing a tire is part of the "theory" classes. It's also fairly straightforward.

Changing oil on the other hand is illegal except in places with special drainage systems (like gas stations) because of the risk of environmental damage from spills, so it's not generally something you can do yourself. This restriction also goes for washing your car I think but some gas stations have places where you can wash your car if you don't want to use a car wash.

Likewise, I'd also like to see less e-waste due to software deprecation (looking at you, Pixel 3).

And where did I say that reparability must be forbidden?

I was saying hat operations like transplanting a more powerful engine into your car is rare and difficult nowadays since grandparent made a reference to cars being easier to upgrade than laptops when that's not always true.

Anyway, swapping an LS into a modern miata is pretty simple and it integrates well due to everything being CANBUS compatible, after a sufficient amount of adapters is applied.