The issue is they wanted hero’s to be roughtly balanced across all ranks.
Buffing turret would make Torb stronger at low ranks, which would be good if his win rate is bad at low ranks (it would be what they would do).
Lets go see.
He has the second highest win rate all the way up to Plat.
Needless to say, they will do nothing to buff him for low ranked play - which a Turret buff would do.
That would make it even weaker in higher ranks and even stronger in lower ones. I like the concept, but it would never fly.