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.
I believe that populism is the reason why Brazil banned gambling websites because in reality, this doesn't solve the problem, it worsens it. In my country, lots of people from Muslim countries come and gamble with millions of dollars, this results in more money in our economy but it's bad for their countries' economies.
By banning 2000 gambling sites, Brazill will lose lots of money. Their citizens will spend money on VPNs and make rich in foreign companies, and then they'll gamble in online casinos, spend money there and make foreign companies rich.