It used to have a very good niche, no other game offered the style where you could raise a monster from a baby and wreck the whole game/journey with it, which is why a lot of old school players have monsters they're super attatched to. The games used to be pretty good, HGSS, Emerald, Colosseum and Platinum all stand on their own pretty well as good games, BW too. But nowadays the games don't really justify the rabid fanbase they've garnered.
So basically, play one of the games I mentioned and see how you feel, they're all great and hold up til this day. But everything starting at gen 6 is strictly for Pokemon addicts only. Play those only if you just absolutely need more Pokemon in your life, as they really don't stand alone as good games at all.
That's my take anyway.
