People were creating computer companies out of the garage in the late 70's 80's because home computing was "new" then. It's too far gone now to do it. desktop computers are in the decline now in favor of smartphones and cloud computing.
The people starting companies out of they're garage these days are building transporters & holodecks!!!!

What is this Amiga Arena that your talking about? Lets look at all three Amiga-like OSs, AROS, MOS, and OS4. All three use atleast AMD gfx driver's and some use drivers for nVidia and Intel. You got a garage company that can roll out GFX cores that are above what the three above gfx chip guys are producing currently? I'm all ears about that one. Lets talk about CPUs with Intel, AMD plus IBM and Motorola, what garage company is cranking out CPUs that are next generation compared to what their current generations are? Again, I'm all ears about that as well.
My point is that no garage company is going to be able to pull ahead of what those giants are spending on yearly R&D budgets.