I have no problem with anybody doing any specialty. Go for it.
That said, nontrads really need to be aggressive in rooting out BS reasons for wanting to be a doctor, wanting to not go DO, wanting to be a subspecialist etc. Idealist delusions and convenient generalizations are adorable over in pre-allo. Those of us over 30, over 40, over 50 who are taking ridiculous risks to get into a ridiculously demanding career had by god better not be kidding ourselves. Had by god better keep working to understand what we're getting ourselves into. Can't go home and let our parents take care of us if we flame out, can we now.
But I've written before about how it's not all that likely we'll know what we're getting into, not in any useful way. If you know what a tesseract is, that's pretty much what you turn into, when you go from premed to med school, again to residency, again to practice. You can't know what you're getting into. A square unaware of the cube.
Watch out for the Third Year Spatula. Assume you'll have your mind flipped like a pancake. You'll be cruising along knowing for sure you don't want to do peds...and then. Sure you don't want to do inpatient. Sure you want to be a surgeon. Sure as hell you don't want to do psych. Your ambitions are, most likely, at the mercy of the physicians who tolerate you in your third year. Who show you what you get to do. Who show you what you DON'T ever want to have to do again. Hope and pray you meet your people in time to pick a specialty in which you get to work with your people. (Strongly recommended: get as much time as you can with non-academic providers. Don't just learn within med ed.)
So. I was a nontrad premed who would not have done med school if I'd known I'd end up in primary care. I still get a jones for the specialty I really wanted.
But goddamn I get to do a whole lot of medicine.
Things I did in FM residency the last month of intern year and the first month of R2: delivered 25 or so babies and managed mother/baby postpartum to discharge to clinic, did my own EKGs in clinic and read them my own damn self (I'll order out that echo though, let's not kid around), sewed up maybe 7 or 8 lacs including a really hard ziggy eyebrow on a 7 year old, did a couple paracenteses, managed transplant referral for a patient with a congenital disease now 40 and miserable she can't have kids, read my own damn xrays because the overnight tele-reads are crap, diagnosed postpartum pre-eclampsia in a lady with a headache too persistent to be from an epidural oh hey look at that proteinuria in that UA y'all didn't think I should order, got a package of homemade caramels from an 87 year old clinic patient (really, really tasty), got slightly less sucky at Spanish, made security do their job and deal with my patient who smokes meth in his hospital bathroom between dialyses, caught an absent red reflex in a newborn, fought admin on behalf of a nurse who got in trouble for my my own stupid mistake, raised hell within the system over a rhabdo patient who didn't get any fluids for 13+ hours, discussed acute inpatient care overnight with about a dozen specialists who didn't have to drive into the hospital because I'm reasonably competent at the basics, did inpatient management for a nephrostomy-whoops-duodenal perf-whoops-still a duodenal perf-whoops-oh hey can you manage the transfer to tertiary now. Didn't intubate anybody recently. Still haven't done a damn cortisone injection. I start my ICU rotation next month. Doing a month of trauma/CC soon. This is what's called "full spectrum" FM. Yada yada.
So what. I have to decide what work I want after residency. Do I want to stick with inpatient, for which my program's recent graduates are getting $350k offers in small but nice hospitals? Do I want to focus on obstetrics and do an extra year to get my c-section count up so I can operate without a supervising grownup in the OR? Do I want to think about the inpatient peds offer I got from a town I might actually like living in? Do I want to take an in-residency stipend (good god I could use it) from a decent health system in return for a couple years' commitment to 4 days of clinic and Q9 call? Do I want to keep doing full spectrum and maybe do clinic+L&D+ED+management in the boonies? Dunno yet.
Hope this helps somebody.