Blockers like deep money. It's tough to find a room for making true blocking bet, when there is only pot behind. When super deep, villain will flat-call more winning range (with his losing range as well) because even minraising can get him into super-gross spot (when his nice bottom set gets shoved 250BB in the face).

I remember a hand, when I played AQ TPTK OOP with 300BB deep. Villain with bottom set (improved to fullhouse on river) flat-called entire way to the river: my flop PSB, turn 2/3 bet. When I made river half-pot blocker, he tanked...and "just" called. He could make a "value minraise" but probably didn't want to lose three buyins in case I had QQ/mid boat.