For someone that isn't a pro, and has more aspirations towards art (or to put it more honestly; taking pretty pictures); I'd say the motivation shouldn't be selling something in a gallery, since that is a pretty hard thing to do in the best times. In my area, the "hip" art scene pretty much lacks photography completely, you hardly ever see a photo in the "hipper" galleries. At our local art fairs (art for normal people), the main photography you see is uber-saturated, over processed pictures of doors (what is up with this trend?), with the occasional over processed, HDR, hypercolor landscape. Very rarely do I see something that I would consider "fine photography". When I do, it is an amazing thing, and made me wish I had the large sums of money these photographers were asking.
My favorite, and yes, this is off topic, was a guy in Jerome, AZ (a small, old mining town, turned hippy and tourist destination) who took pictures of rust and lichen on old mining machinery, using a large format camera, and a macro lens. Beautiful stuff, if you had the $2,000+ to buy a print. Another guy at our big art fair, took awesome macro shots of rocks (they looked like abstract art). At this same fair though, my girlfriend was pointing at random photos and saying "why don't you sell your stuff, you are so much better", which was a nice ego boost, and a sad statement on the state of the photography at the location.
But at the art fair, much of the painting were also very... consumer focused? Painting of doors, basically. Art is a cultural thing, and is completely dependent on transient, and arbitrary factors. In three years photos could be all the rage, though I doubt it since photography is seen as "banal" thanks to the fact that most people have 20 cameras built into every device they own, and the internet is completely awash in photos. It somewhat cheapens the idea of "fine art" photography.
For myself, I take pictures because I love doing it. I don't care if I ever get rich, the pleasure I get from a really good shot is worth the hassle and expense of the gear. Sharing this with my friends and family is just a bonus, which makes it even more worth while. Don't get me wrong, if anyone ever offered me money for a photo, I'd be about as happy as I could. Not so much for the money though, but more for the ego-boosting recognition ("I'm good at something!")
More on topic, in the beginning of digital, I do think APS-C was a compromise, since 35mm sensors would have been hugely cost prohibitive. But now there are some benefits that it has, even its limitations can be benefits occasionally (more DOF isn't a bad thing for us macro shooters, all of my lenses are longer which can be a nice thing), even M43 has some benefits over APS-C and FF. I don't think there is a perfect format. If all the formats were the same price, people would still choose M43 and APS-C.
