There is a lot of games that require 6GB+ vram on max texture setting even at 1080P.
Rise of the tomb raider, doom 2016, Lords of fallen, shadow of mordor to name few and some games won't let you even enable max texture setting unless you actually have 6GB vram.
Benchmarks don't tell the whole story it's when you stars playing game there are moments where you gonna get terrible stuttering but it's not all the time.
Now maybe some people can live with stuff like that but I can't.
All I can hear here is overkill this overkill that to which I say ********.
For me I need loads of performance buffer so even in those few most demanding moments in games everything stays above 60fps and that's what I call smooth gameplay.
Then the 1060 is not the card for you either.