My partner and I have been working diligently at trying to speed up our Ubiquiti Unifi wireless network. It ran at good speeds 18 months ago and is now slow. We've been in contact with Ubiquiti and have been systematically implementing changes in an effort to improve wireless speeds (record average speed, implement configuration change, record average speed,....).
Our boss suggested that we implement "blocking technology" to "tamp out" nearby wireless networks. (There are many; the office is located in downtown Denver.) I suppose there could be technologies out there that detect EM signals in the 802.11 range (2.4 or 5.0 GHz) and generate signals that are 180 degrees out-of-phase with the detected signals, producing destructive interference, but I would think the list of possible complications and the possible downsides of such technologies would out-weigh the upside.
Let me know if I'm wrong.