Since I started bitcoin in 2015 there are already bitcoin gambling sites and today they are still existing. I'm just thinking if gambling is one of the factors in increasing the bitcoin's value.
I don't know how do you get that thinking or from what source to start this topic, but gambling never gonna affect something's value. Gambling is a method for you to earn something from what other people lose or get something from the stake you bet.
It won't ever make something value gone up because it doesn't have any value in it. Never.