Who is to blame for the bad stuff of the Obummer years? Much of that is debatable. Contrary to the regular assertions by the wingnut brigade, Obama isn't a dictator and he has faced a hostile Congress and a somewhat hostile Supreme Court. Some things were genuinely beyond his control. I have my opinions on some of that stuff, as all of you do I'm sure, but as I wrote, it's debatable how much better Ideal President Obama could have done over Actual President Obama, given the situation.
Still there is one thing which can really be pinned on him. His administration not only had authority, but oodles of money that they never got around to spending. It was supposed to help deal with the foreclosure crisis. They did not. Instead they let the narrative about innocent bankers preyed upon by supergenius poor people with poor credit ratings survive, letting the criminal fraud go on and on and on and on. They could have stopped it. They didn't.