There is a lot of gambling site now are instant withdraw because as a player Im looking also for that. But now I don't they have some gambling site who have need more hours before payout sent almost gambling site now are instant withdrawal . Best example for that is Stake after requesting payout they sent it directly to your account instant no waiting needed.
Supposedly it must be instant withdrawal but some gambling sites never have.
It sometimes we consider the amount we pay cause it could be more prioritize those withdrawal transactions that have high fees. But of course, we usually set into the small amount and so we can't expect that it will arrive in our wallet instantly, it will surely take minutes or hours.