I'm 37, fwiw.
I don't consider myself an expert, but I ski terrain in Colorado marked with <E><X> and don't give it a second thought, so I'm probably okay. Also I take a ton of lessons thanks to Breck's fantastic club program, so I know enough to have a pretty good idea of when I'm skiing well, when I'm not, and what I want to change/fix.
Many days, I don't fall at all. Some days, I fall multiple times. None of them have been terribly bad. The worst was not seeing a gully, hitting the far side with my tips, and getting flipped backwards so that the back of my head hit the (hard) snow. In retrospect, I had all the symptoms of a concussion. So I've been pretty lucky. I did just tear a four inch gash in my brand new Arcteryx pants, which may have been the most emotionally damaging fall so far. That was because I was lured by fresh powder, not knowing it was all shark fins just beneath.
I agree with a lot of the posts here - I think the falls come in three categories: 1) not paying attention, 2) pushing myself, and 3) intentionally accepting risk by, say, skiing into untracked snow in the trees where something could certainly grab my ski.
Not sure if it's a sub-category of pushing myself, but a common mode of fall for me is skiing something that I find intimidating, therefore falling back on bad habits like not using my edges properly, twisting my body, leaning back, dragging my poles, initiating a turn with a stem, initiating a turn by lifting my inside ski, or initiating a turn by ... you know what, I think almost all of these falls can be covered by "initiating a turn poorly." The first turn definitely sets the tone.
Anyway, what I wanted to say was, I observed in the last few days that when I'm having a confident day, a fall barely even captures my attention. I just laugh, pop up, and barely remember it. When I'm having an anxious day, a fall feels like an omen or confirmation that something is terribly wrong with my skiing that day. It reminds me of the Buddhist parable about the monk who carries the women across the river. Anyway, my goal is to just let go of those falls the way I do on my good days. Attempting to ski conservatively, in my experience, has always resulted in me skiing poorly. On the contrary, I'm trying to learn to loosen fear's grip and take a more direct line. This means I'll be going faster, and therefore that falls will be more risky. But I can't get where I want to go in skiing without taking that risk.