Could toplane Turrets Reduce Damage Taken to champions if the source is outside the turrets range?

Ranged toplaners are very frustrating to play against as a melee champion, and often the safest way to deal with it is try to utilize any sustain you can and farm under tower, but often you get punished under tower even then, and it sucks.

I imagine the buff acting kind of like this

_For the first 6-10 minutes of the game, if you are in turret range for at least 2-4 seconds, you gain a buff that reduces incoming damage by 20-35% (or flat damage, like 10-30) so long as the source is outside turret range. If you leave tower range, you lose the active reduction, however if you re-enter range within 1-2 seconds the buff will return instantly instead of having to wait again. (More forgiving if you are hovering at the border range) _

What are your thoughts on this?