Doctors often don’t emphasize diet lifestyle changes because patients never follow through.

I don’t want to take away from calling out corruption and kickbacks because that is a huge problem but developing meds that relieve symptoms is already an incredibly difficult challenge for research, cures, even more so. 

In my decent career in science I’ve never heard one biomed scientist say something along the lines of “Lets make a drug that doesn’t cure someone, it’ll make us more money 😈” unless they were joking.