Fret not! I listened to the same when I was in middle- and high-school, and eventually reached the conclusion that what ultimately bound the music under the "alternative" label together was nothing more than pseudo-rebellious Gen-X marketing aesthetics, rather than some actual stylistic association. It was mostly all just "rock" - as a genre, not a style - in a different outfit, at the end of the day.

Of course "alternatives" to rock still exist, but that's an always-moving target; the "rock" of today is - funny enough, considering your username - the countervailing, ever-expanding umbrella that amalgamates all that is no longer "alternative," the very thing which the new and non-traditional forms innately oppose themselves to. The "alternative" of today is, for one, not called that anymore, and two, not to be found by any means in the same channels through which it once flowed.

Perhaps the broad strokes of society just aren't ready for it? Perhaps they won't be until it's "over," moved on to something else - perpetually ahead of the curve. But it's out there, if you know where to look and actually do so. Perhaps this is all tangential, since ultimately your point here is about radio, but I think the general consensus is that radio is more or less a dead medium for anything fresh and less-than-commercialized (not that I think it will necessarily stay that way forever - you could look at the vinyl boom for a potential analogy).

Anyway, I like your writing; I read your intro post and you're definitely the kind of person I could stand to see a lot more from on Steemit, so I've got you followed. I write a lot about music of all kinds in my column The Harmonic Series, and I have a hunch you might enjoy it. Here's a link to my 2017 Top 10 Albums list, check it out if that sounds interesting to you.