Depends if they are done properly or not. If they just put up a wall, then no. If they build a couple of different barriers then yes, they do work very well.
unfortunately you or me or the authorities don't get to decide if they work well or not. the only people who can decide that is the people being affected by the noise. you have to go with what they say.
As for the home values, goes back to what I said above, if you move into an area with a very hands off state of mind for planing / zoning, this is always the risk you have. Sorry, but no sympathy from me on that.
it doesn't mean the laws don't need to be changed then. new zoning regulations to deal with noise. plus many of these people you don't seem to understand probably been living there before bitcoin even got invented. i bet they don't like satoshi now though. i wonder if satoshi would feel responsible for kind of wrecking their lives....