From what I remember, President Obama was not dictator nor did he have the sole proprietorship of any health insurance company. What the for profit insurance companies decided to do was not within the power of the POTUS.
The lobbyists from the for-profit health insurance business said what the politicians wanted to hear, then, they changed the game. They decided to drop people, cancel policies, re-negotiate with health care providers, raise premiums, etc.
There was not one, single line in the ACA that required for profit health insurance companies to do any of those things.
I have had the same PCP since before the ACA. Had a good group policy before ACA, have the same policy now. No one I know was forced to change physicians.