You are wrong my friend, it will affect them, the higher the tax, the higher the discouragement, this is normal economics everywhere in the world.
But it won’t completely stop gamblers. There are actually countries where gambling is banned some gamblers still find ways to keep betting. I think , when gambling is part of the culture (as it is in some countries), it’s tough to break that cycle. The most a government can do is try to discourage it, but how effective is that really? They might just be pushing tax revenue away. With the popularity of online casinos, no matter what kind of restrictions are in place, there’s always a way for someone resourceful enough to gamble.