I don’t think you could get OEM parts that would actually fit in that space tbh. Also the guaranteed software support from valve, and set spec list allowing devs to optimize for it are some pretty huge bonuses over other prebuilts. I’m not saying building your own comp is a bad idea, but for the average user who just wants to be able to game at medium settings in most games, this has some pretty major advantages.

Ah, maybe they could make some cool prebuilt with Linux already built in. Hmm and make it small enough to fit under a TV in a small shelf 🤔

Sorry but you can easily do that. The average person cannot. Most people would have to do multiple weeks of research into what different parts of a computer even are to have any hope of building a PC. Lemmy is one of the most out of touch places I’ve ever seen as far as tech literacy goes. The average person likely couldn’t even tell you what an operating system is, let alone know what Linux is.