>all the FiM talk.
For me, it's just that FiM shows characters that look and feel real. You see the shadow sides of them, their dark sides, and it comes off as natural. Teen Titans did the same, but then again, that was an awesome show.
I guess the main reason I started watching it is because of the familiarity, and I think a lot of people my age have the same reason, but don't realise it. The recurring moral of FiM, as I see it, is that you are more than your gimmick. Just because you think you are one thing, or others expect you to be, doesn't mean you can't be something else. That's my guess why so many college-aged people watch it: right around college is the age where you realise the person you acted like in high school isn't all you are, and cannot be if you wish to be successful.
Other shows do not do this, at least not as consistently or subtly, not without making the dialogue simpler. The Maya reboot is pretty close, but it's still toned down for kids. Teen Titans did it, but it had the context of superheroes and villains, so it's further from real life. In FiM, there are situations that are cartoon versions of real life, but closer to it than usual.