To tinker with cars as a hobby, one requires property, a garage (particularly one big enough to work in, probably at least two bays so you have somewhere to park your commuter vehicle while your hobby vehicle sits immobile in the second bay), cabinets & walls full of tools, etc.

So right off the bat, these requirements are going to price out most teens & young men unless they live with parents who own these assets, live rurally, have a father that owns a business, etc.

Another problem with living like a bugman in a tiny box in the sky.