I understand your point. I think this comes down to how you approach things and what you enjoy in medicine. FP does have variety in diagnosis, and patient population, but personally I'm not too keen on treating HTN and DM most of the day, everyday. Overall, it does have less grey-area than psych.... except maybe Geri med, there's a lot of grey there.
I do want to highlight the above for any medical students or folks trying to discern a specialty. Most of any medical field (or any job) is taken up by bread and butter conditions, of course with some variety in presentation from person to person and some more unusual stuff sprinkled in.
Outpatient family practice: lots of DM, HTN, a couple of other chronic conditions.
Outpatient psych: depression, anxiety, maybe some psychosis or BPAD
Hospitalist medicine: ACS rule outs, pneumonia, COPD, heart failure.
General surgery: cholecystectomies, appendectomies, and hernia repairs
ICU medicine: septic shock, COPD w/ respiratory failure, DKA
I'm not at all trying to denigrate any of the above fields in any way by saying this! Getting good at bread and butter issues in your field
is literally why we have specialists, and believe me I'm not trying to take out anyone's gallbladder on the psych floor. It's just crucially important to realize that every field will have some routine, and part of choosing a field is choosing what kind of bread and butter you want to deal with. If you don't find the bread and butter of psych interesting, like futuredo, that's totally fine! Just realize that literally every single field (including the sexy exciting ones like surgery or intensive care) will be mostly "routine" cases, with some differences in presentation, the kind of patient that has the disease, etc, and that chasing zebras or managing exotic things will be the minority of your time wherever you practice. Medicine is not House, MD.