The RJ-45 connector is an open standard that can carry basically anything—internet, video, audio, low-level data, etc—at a high bandwidth and with low latency. Why can't we have a wireless standard that does that?

I want non crappy Bluetooth mice that don't require a separate USB dongle. :(

Edit: To be clear, I'm sure ethernet cables are an entirely different thing and there's actually a very good reason why wireless makes everything more complicated. But, well, maybe that's one of the reasons people would like to stick with wires.