Sports fandom is weird in general. The only sport I genuinely love is baseball; I grew up watching and following it, the Braves started their extended run while I was just entering my teenage years so I had a really good team to root for. We rooted for them when they sucked ass during the mid/late 80's too, though.
The NFL I never got into until my mid-20's, and by that point I just liked the game and was following it for fantasy purposes. The Falcons were consistently mediocre back then. I still don't have a team I really root for; I say I root for the Pats to troll people, also because I had Brady/Moss/Welker on my fantasy team during the 16-0 season. I kind of keep up with the Falcons, but not too well.
Basketball is just meh for me... watched Jordan during his peak because it was a spectacle to behold, don't really watch too much these days.
College sports of all varieties are for functional distinguished mentally-challenged fellows.