[simion314]

> I'm not sure what you mean by a modular car design, but you definitely can't fit any motors with any battery in any frame, that will just make for a car with terrible performance.

Not any in any, but some in some is already possible, some Renault cars share parts for example with Dacia. But other companies tweak their design each yer, they change how the head lights look, shapes change, then some other inside parts shape needs to change so you got people having to redesign, re-test each year new filters and piping/hosing (this is the ones I am familiar with), Other shitty thing that happens is patents, some company gets a patent for some pretty obvious thing, now if you want to make spare parts for those cars you need to work around dose patents - a lot of work and expenses to be able to offer a different choice to the consumer.

The reason the engines and other parts can't be share is design and recently DRM, for sure you won't be able to install unofficial wheels on your fancy car without breaking some DRM protection(but is for your safety /s).