> It never will be though. Whatever frequencies you can do wirelessly you can do over a wire without the interference of other users using the same frequency at the same time.

this is true in principle, but not necessarily in practice. I suspect it will hold for the near/medium future, but I can imagine a world where much more money is invested in improving mobile networks than home cable connections, causing the latter to stagnate.

most "normal" people I know don't even own a desktop computer. there are no devices in their homes that connect via ethernet (or even have an ethernet port without a dongle!). at a certain point, it might make sense to ditch the home modem/router altogether and scale up wifi networks to the point where they basically merge with cellular.