When I was a teenager I desperately wanted a 35 mm SLR. I bought photography magazines, read all the reviews. For me, price was the biggest factor, so I was looking at Pentax K1000-class cameras, which could be had then for a little over $100 with a lens.
The thing that struck me then, and still strikes me today, is the sheer amount of brand snobbishness in photography. Back then, you weren't a “real” photographer”, and you weren't using a “real” camera, unless you were shooting Nikon, Canon, or Leica. And of those, only the Canons were at all affordable. And yet, you could throw the exact same Ektachrome in any 35 mm camera, grab a good prime lens, and shoot exactly the same pictures. No one on earth could tell whether you had taken it with a Leica or a Pentax.
And the same thing is true today. Today, because most of my photography (which is, again, mediocre) is travel photography, I shoot an Olympus em-10 with a $300 lens most of the time. It's small and it won't break my heart if it gets broken or stolen. The m43 system has a ton of great lenses and high quality camera bodies. With the different sensors it's now possible, in theory, to even tell the difference between pictures shot on an Olympus and a FF Nikon, but in practice 99% of photographers won't ever realize those differences. But it isn't a Nikon or a Leica, so I'm still not using a “real” camera.
Anyway, my point is this: to be perfectly honest, I doubt the ability of the field to choose standards based in technical merit. There are decent reasons to desire FF cameras over APS or m43 — the availability of a lot of legacy lens designs, for instance — but as far as I can tell that isn't the real reason it's taking off. It's taking off because it's now possible to drop ten grand on such a system.
Sorry for the cynicism. But I've been told so often that I'm not using a real camera that I finally just decided to ignore the hype and enjoy taking pictures.