In bronze, even if Blitz hooks you, you can still escape with either minimal HP loss or without burning flash (if you have mobility). I've done it as high up as gold.
In plat+, hooked = dead or burn flash + back.
In bronze, even if Blitz hooks you and you die, the enemy team can't capitalize as hard and probably won't even get every cs.
In plat+, if Blitz hooks you and you die, they zone your lane partner from even EXP, push wave into tower, dive your lane partner while you are still walking back to lane then zone you again, or they take your turret, roam mid, get another kill, take drag, then the enemy mid is now bot and taking your t2.
It's all about making maximum impact of those hooks.