It's absolutely the WWE's version of the minor leaguesl. In fact, I use that term to describe it to people. When I first caught it, in 2014, I thought it was worthless for the same reason. Plus, Mojo Rawley and Adam Rose were featured. I was also a little annoyed how it had a lot of Internets Buzz and people were raving about it. I think I started to get into it around the time Kevin Owens debuted (late 2014/early 2015). I was bummed when Owens left, since I loved his run as Assh*le Champ.
People have short shelf-lives in NXT, which stinks. As we've mentioned, a relatively small percentage actually make an impact on the main rosters. That will not hurt or render obsolete any time you've invested in watching NXT. So, just enjoy it for what it is. Although the constant roster swap-outs remind me a little of the old territories, or even ECW in the 90's.
As for stuff you don't watch: we've got a new thread for that!