Why aren't wireless screens/monitors available yet?
I have 2 screens connected to my computer at work in addition to my charger coupled with adapters and what not (MBP so all USB C). Dangling all those cables got me wondering why and if/when will we have wireless screens so that we can practically be wire-free and can move around/connect to other desks seamlessly.
Huge amount of data being passed to the monitors 1-3 Gb/s, having latency within 1/60th of a second (60hz) is not trivial either especially keeping that latency stable
There was an app out several years ago where you could use your iPad as a second screen with a macbook. A friend used it and said it was useable for working at a coffee shop.
Mostly bandwidth, reliability and interference robustness. The Wii U certainly proves it's possible, although that's streaming 1280x720. Displays at much higher resolutions require considerably higher bandwidth and are much more expensive as a result. Plus, if your screen is in one place, the source is likely to be there too, so why not just make it more reliable with a cable.
The real problem sounds like you are stuck having to hot-desk or some other foolishness. A dedicated workstation should not be a luxury.
Airplay works pretty okay. Bandwidth and latency can reduce quality substantially though.