Why is Bane not picked in basically every game?

So this is something that has baffled me for quite some time. Full disclosure, I'm a 2k MMR player, so I might not get the intricacies that this boils down to, but my analysis is basically the following: Bane is an extremely powerful disabling support, with a very powerful laning phase, and great lategame catch and disable that can literally win your team a teamfight. Played with a decent amount of skill, I'm struggling to see why a hero like this is not picked/banned in pretty much every game.

Enfeeble – lowers attack, cast range and HP regen for a pretty long duration. This can cripple a carry/caster that used BKB/doesn't have BKB for most of a teamfight. It can also really mess up early engagements in the lane.

Brain Sap – really good trading spell in lane. Lategame it's just a mini-nuke, but the ability to just spam it on 8s cooldown just seems busted even in the midgame, when it heals you for like 200 health.

Nightmare – Great catch ability, a very strong tool for engage/disengage and sometimes forcing a fight. You being able to hit the target is just a small bonus, but the ability itself is a great point & click initiation.

Fiend's Grip – Amazing BKB piercing disable, that while it keep you stationary, makes sure that the enemy carry cannot move either. I would trade my Pos5 for the enemy's Pos1 in most teamfights.

So having said all of that, why is Bane ACTUALLY not picked everywhere? What am I missing?