Let's take a railway analogy. Obama was elected to drive the train for four years a couple of times over, during his tenure things would be better on the train. However, the points, signals and power to the track was not something that was ever to be in his control, the train journey would be pretty much whatever the 'deep state' of intelligence agencies and their cronies wanted.
Like all previous train drivers Obama did not jump any signals or stop the train to hop out the cab and manually shift the points to get the train on the other track. He did a professional job of steering the train along without running too many people over or derailing the show. His predecessors were generally not as good at these finer details. Perhaps what Obama was best at was doing the announcements over the intercom, the passengers found him to be very funny and charming and all those good things.
Although we are all experts on trains - where they go, what the schedule is and what the seats are like, the reality of the coffee and so on, most of us are utterly clueless about what is in any of those boxes at the side of the track or how it all works.
If I was one of those people that always wanted to be train driver, and, if I had to put together a popular platform to be elected, I could make all kinds of promises, e.g. to floor it at 125 mph and put on some non-stop direct services with some buyable-in-able idea that it would all work out wonderfully. If I knew about the railway and the state of the track, or anything about those grey boxes, then I would not be issuing these cheques that cannot be cashed. Being a 'nice person' would not be enough, clueless me would not be able to take on the constraints of the infrastructure to deliver those 125mph direct trains.
It is easy to be matter of fact in a railway analogy when it comes to the problems of the system, with politics the 'deep state' is the 'problems of the system' and this is best discussed 'matter of fact' rather than as some mumbled conspiracy story.
You are not going to revolutionise transport by being a train driver even if you are the best guy for driving the train. Obama was the best guy for driving the train down the 'deep state' tracks.