Your delusional if you think GPU and ASIC mining is comparable. ANYONE can buy a gpu and fire up a rig. yeah maybe the big boys could get thier GPUs from the source maybe 50% cheaper than the regular joe but at least everyone has a shot.
While you are correct that anyone can buy a gpu and fire up a rig the reality doesn't work like this. People will need a full PC to use the GPU, then they wouldn't be able to play any game on that PC, then they need to keep the PC running 24/7 and so on. There are many variables that just don't work. The big boys would be able to run the GPUs 24/7 while the home user only a couple of hours per day. The home user will need to upgrade his home electric circuit if he wants to fire up more rigs and he will need space and cooling for them. It's an added costs that the big boys can cut it by a lot using datacenters. There are many downsides to your scenario.
Well, almost everyone has a PC.
PC usage is "decentralized" and we are not all using dumb terminals, which was envisioned in 60ies and 70ies.
I think that BTc/whatever coin decentralization is possible along the same line-a coin that has strictly CPU (not even GPU) algorithm without scaling.
I would think that it should be possible.
Yeah, but a GPU that mines for a decent speed costs money, then you need a good power supply, then you won't be able to play games on that PC while mining. You are asking home owners to invest in a GPU that will mine maybe less than 8 hours per day. What we really need for decentralization is something like the 21 inc computer. Something that can be set to plug-and-forget, not something that you use daily and that is prone to damage if you run it for 24/7 for 1-2 straight years.