This is silly. Psychiatrist potential can go as far as he or she wants, just as in Fam med. You can't say potential is a lot higher, because large revenue streams are possible in both fields. It's completely dependent on the individual. How much you can make depends on your drive, opportunities, and creativity. Have you heard of a psychiatrist making more than a brain surgeon? I have. Around here brain surgeons make $500,000. I know two psychiatrists who are directors of hospitals, and they make huge sums, over $700,000. (Surgeons are too busy to direct hospitals imho.) I know of another who runs a multigroup practice, again big money. I know another who does work for a pharmaceutical company. You make as much as you want. You can slice the loaf any number of ways. Psychiatry is a great field, and it gives you the flexibility and time to take on leadership and managerial roles. Stop being scared about it, go out there, and do it!
Start looking at the majority of family med docs, instead of the highest paid which are outliers.