As more people drop cable television in favor of streaming: every TV, computer, phone, game system, etc.. will be using the network at the same time. Wireless may never be able to keep up with the reliability and stability ethernet offers and the bandwidth we're going to be using soon. The 2.4ghz spectrum is already overloaded, the 5ghz spectrum will soon be just as overloaded. Sure 5ghz can in theory do a gigabit --though we know it is nowhere near that in the real world -- but the range is atrocious compared to the lower frequencies. Imagine a house in a busy neighborhood with 20 houses trying to share the same spectrum, one of the houses has 4 screens streaming 4k, little Becky is Skyping with her boyfriend, little Johnny streams his favorite Twitch broadcaster while streaming his own gameplay at the same time. Wireless? lol.
MoCA networking is taking off because people are sick of wireless and they aren't willing to pay the costs to upgrade the cabling inside their walls. New construction in developments are dropping cat6 in every room.
Intel is promising 10gig ethernet cards for less than $100 soon, you can already pick them up for about $150.
I'm not saying it is happening tomorrow, if I had to guess, I'd say 3-5 years and it'll be as common as gigabit is now.
You can say the cost isn't worth it, but, if you're building $100,000 house, your walls are open, and its an extra $100 to run cat6, the choice is obvious. And you can call it a delusion, but, people said the same thing about going to ISDN, then DSL, then cable internet, they're saying it now about going with google fiber. Personally, to expect anything other than speeds to increase is delusional.
Do you realize how silly it sounds to say "10GigE is almost exclusively data center...and that's where it will stay." You sound like a crazy person.