I have, have you? General approval ratings for Senators and Representatives tend to be extremely high, and in turn the reelection rate of incumbents is quite high as well. Or did you mean "approval of Congress as a whole"? If you did that's silly because people do not vote for Congress as a whole, people vote for their own representatives within that body. Since the population is not perfectly uniform in its beliefs or priorities, that means inevitably even the most perfect hard working representatives will certainly not get their way all the time, and will probably flat out lose fights sometimes, which means that the body as a whole will be making one group or another mad almost all of the time. That's the reality of organizing a diverse group of people though towards goals too big for them to handle individually. It would make no difference for any system of governance whatsoever short of some sort of compulsive mind control, the population will be angry about decisions some of the time.

If you were going to object to GP, a better (scarier) counter point would be that as technological advancement has ever more eclipsed individual human power, it's not at all guaranteed that at some point a totalitarian regime couldn't emerge backed (and/or run) by sufficient tech to be internally long term stable even against the wishes of the majority population. Or for another side, that could simply do away with said majority of the population.