IIRC, the first boomer US president was Bill Clinton, who was in his 40s when elected in 1992. Members of Congress trend older, so let's pick a reasonable year and say that's when the Boomers took over government. How about 1994 or 1996? Is that reasonable?
I suggest that the following factors were entrenched or in progress long before the boomers took over:
1) A structural federal deficit and growing national debt
2) Globalization, automation, and the decline of US manufacturing jobs
3) Subsidized mortgages, encouraging houses to become bigger and bigger, and for there to be fewer "starter" homes
4) Universities becoming bloated resorts offering many useless degrees that were increasingly unaffordable
5) The shift from more affordable cars to luxury SUVs
6) Suburban sprawl, a lifestyle design which manages to increase both transportation and infrastructure costs simultaneously
7) Crime actually peaked just before the boomers took over
8) The American middle class was in decline since the early 1970s
9) Healthcare inflation was already becoming a major issue.
10) Consumerism as the dominant cultural value
11) Deteriorating quality of journalism
12) The shift toward processed foods and fast food
So it was really the self-described "Greatest Generation" and the "Silent Generation" who were in charge when whatever policy or cultural changes occurred that precipitated these issues. They retired from their leadership roles in the 1990s when the crises we now face were at an embryonic level. Sure these generations did some important things, such as not letting the cold war get hot, enacting public health improvements, promoting civil rights and women's rights, improving education, defeating inflation, removing lead from gasoline, discouraging smoking, and starting to think about environmental protection. But they also authored many of the policies and cultural norms which led to the problems on this list.
TL;DR: It's your dead grandpa's fault.