Survey/public opinion polls do bear out that trust in institutions was much higher in the 60s and 70s (and likely before that too) and began to decline in the 70s. I do agree with that. However, politics has always been an "us vs. them" game. If you think that anti-immigrant fervor, for example, is really high today, look at immigration to the United States in the early 20th Century. That was a gigantic backlash against legal immigration.
Perhaps it's because I was born and raised in this era of lower trust in institutions, but I don't see more skepticism of institutions as necessarily a bad thing. It seems like the greater trust people had in government, the media, big business, etc. in the past was misplaced - it isn't as if those entities were more moral 50 years ago than they are today...people just trusted them more and now they don't. I don't think it's a bad thing to look at large, powerful institutions and have the stance that you'll trust them after they've done something to earn your trust.