Europeans have problems with NIMBY, but not nearly to the extent that the US does. It takes about 1/5 as much money to construct a mile of track in France as in the US, and 1/10 in Spain. My guess is that part of the point of the Hyperloop is to get around land use restrictions by going over them, and the largest payoff for that would be in the US where conventional land-based transport is hardest.
With regards to NIMBY I'd be very interested in how much external noise would be generated. If it's silent from the outside and all it takes is a nice line of trees to conceal it completely I can't imagine people would have that much of an issue with it.
