I wish there were noise cancelling surround speakers, like the headphones. Everyone would buy a set. They'd even be popular with married couples!
As far as a steady noise to drown out an irregular noise - the problem is, the steady noise has to be in the right frequency range, sure, but it also needs enough amplitude to overcome the other sounds. That's why I wish it was targeted via a mic and dsp, like the nc headphones, which are bulky and and if slept in, lead to a stiff neck. I don't know of any product like noise cancelling speakers. Anyone?
The usual blunt force method (judging by view count) is one of those 10 hour YouTube videos offering various and sundry relaxing sounds, loud enough (or speakers close enough) to blend with the neighbors' cacophony. It's like building jetties. Then the next neighbor downstream has to drown out your sound, and the further neighbor has to drown out the next neighbor, and so on down the line. Pretty soon you have a beach full of jetties. But, everyone prefers their own brand, so it works out, kinda.