Too good to be true? Certainly it is a reasonable possibility but as pointed out there are drawbacks and limitations that would limit its usefulness.
Initially I thought of the possibility of using infrared or even ultraviolet, but then realized the key to this technology is using the entire
VISIBLE spectrum and IR or UV would defeat the purpose.
It might be viable distribution media for a LAN in an open office or laboratory environments with high ceilings and no walls — not even cubicles. One article suggests using it in hospitals where WiFi signals may interfere with sensitive monitoring equipment but from my recent experience in a hospital where I was on a heart monitor for five days, it was bad enough with the nurses and techs coming in every couple of hours throughout the night with the room lights off. I think after a couple of days with the lights on 24x7 sleep deprivation could easily become a more serious problem than the one I was initially admitted with. Not only that but how would you distribute that bandwidth from room to room — or would you convert the entire hospital, including toilets(?), into a single open bay?
As for home use, what benefit would there be to offset the limitations? Even fiber optic to the wall cannot deliver that much bandwidth and how much device to device traffic do you have in your home? The vast bulk of that bandwidth would be unneeded and go unused.
For increases in internet and home LAN speeds any time soon, I would invest in new data compression technologies which would allow sending more data within existing bandwidth regardless of the carrier technology. But then I bought Apple at $9.50 a share, so what do I know?