IMHO there is a huge disconnect between the output and the value to society in the humanities: dissertations that nobody reads, papers published in journals nobody reads, books published that nobody reads--all of this stuff is created for the single selfish purpose of advancing one's career, not expanding the boundaries of humanity's collective store of useful knowledge. Once written, this stuff is ignored forever because it is un-useful, un-commercializable, uninteresting to anyone except the writer and their half-dozen academic peers; it's pure make-work. It could cease with no real negative impact to anybody but the people whose careers have been built on churning it out. It's a giant circle jerk where people write useless nonsense in order to impress other people with political power over their careers who pretend to care because they themselves only write useless nonsense and know they must go through the same process. It is insular, self-serving, and it hurts the country for so many resources and so much time to be wasted on the academic equivalent of digging ditches and filling them back in again.
I understand exactly what you mean, PS!! I actually started out with a math sciences undergraduate degree, and got off that track after I realized the goal was a constant circle of making up problems and solving them, with the solutions so intricate and opaque that they'd never, ever see actual use. So it's not precisely the same as humanities...there are some in the humanities who do useful work like translating the Book of Judas. Political science, however, is the world's biggest headache. I took a poli sci course freshman year and almost failed it, I thought it was so ridiculous. Thank heavens for freshman pass/fail...
Not all scientists are productive, and many rely on obfuscation to impress other people into thinking they're saying something with great significance. If I read a paper and can't understand it, I know the author is just trying to snow me, and I move on.
As far as pay and quality of life improving after tenure: I will let you know once the rubicon is crossed, and hope you're right!! I suspect that's the case although not sure the actual impact in a clinical department. One thing I did hear about is that tenured faculty get a private "tenure fund" that the university kicks $100K into every year. You can spend it on whatever you want, but my chair advised banking it for lean times when grant funding runs dry. Having that backup is going to be a big confidence booster.
Small correction - grants are not for supplementing salary, but for funding part of it so you can spend your time on research - otherwise you have to spend your time earning money in other ways to justify your salary, like seeing patients. So there are a lot of people working as hard as a private practice physician for half the pay, which I think is just plain stupid. Not surprising that these people are bitter, and consequently these are the ones playing the petty political games.
However, provided you heed PS's and my words of warning...jump in, the water's fine. And now I remember why I started going off on this tangent in the first place: an academic career does greatly benefit from attending high quality (Ivy or equivalent) schools. You can get away with a state school as an undergrad, but for graduate and/or professional school you need to aim high. To avoid getting killed with student loans, a prospective physician scientist should consider an MD/PhD program, where you get full funding to get both degrees from one institution - usually 2 years MD, then PhD, then finish MD. Long haul and the programs are tough to get into, but the rewards are great.