I wonder how much of it is laziness / refusal to take responsibility.
Small scale you have CEOs or other leaders that can't or do not want to do everything and dole out the responsibility to others. Not bad in and of itself but often they refuse to take ultimate responsibility when their underlings screw up.
On the national stage you have Congress giving over a lot of their power to the bureaucracies so when people don't want something they don't need to vote for it. Some department or agency just makes it happen. All that power ending up at the federal level for the same reason, people, cities, states, etc. getting the Feds to do stuff they can't or won't do for themselves.
The more this goes on, it creates a huge number of positions for people to fill that tend to pay decently, do not require a lot of brains or work, and, let people play petty tyrant without any real accountability. The perfect place for these midwits.