You don't think the average PC only having 2 GB vram has anything to do with consoles? Consoles set the standard so you don't really need anymore than 2 right now. Now recently we've seen cards with 4,6 and even 12 GB of vram. Strangely it coincides with the ps4 and xbone releases. Coincidence, I think not. Now that consoles, which games are made for can support more demanding games you'll see PC median hardware creep up because it will need to.
IM not sure if you forgot PC history or haven't been gaming long enough to know but low end pc's haven't held back video games. If you remember before virtually every game became cross platform we had video cards releasing every 6 months and upgrade cycles of 6 months to a year if you wanted to play the latest and greatest at max settings.
Think back to when the 3dfx voodoo cards were released. Dev's didn't shun the cards because most PC gamers didn't have them. They embraced them and coded for them, leaving setting for people that didn't have them as well. I remember switching my games between 3dfx on and off and marveling at the change in graphics. What happened as a result people started upgrading because they wanted to play those games.
That's the way it should work. Software pushing hardware and hardware advances allowing software to grow. That's what the PC encourages to happen. When you have consoles with the same hardware for 10 years all you can hope for is optimization improvements. Nothing pushes anything.
That's how consoles hold back gaming. It creates stagnation, there's no software pushing hardware or hardware encouraging software growth until the next console cycle 10 years from now.
So, I think if we didn't have consoles you'd see a very different PC median spec but with long console cycles there's just no need.