There's a reason these industries are hard and should be hard - these are serious industries with serious consequences. Health care - screw it up and you kill someone. Drones - screw it up and you kill someone. Cars - screw it up and you kill someone. Finance - screw it up and you lose the retirement savings of your investors.
These are not games to be played by unsophisticated people or green entrepreneurs. This does not mean that the extant incumbents are any good - it merely means that new players does not automatically confer innovation goodness (see natural monopolies/booms).