And it's about the competition as well as there are a lot of individuals too who try to be affiliate and went the whole nine yards but was not successful in the end. In short, this is a niche market and unless you are a authority, a well known personality in the gambling world, it's very hard to earn money thru this method. I also did this before, maybe got 1-2 active gamblers, earn some, but it's not like you are going to survived from it. Not saying that we can't be successful, but you really need to work very hard, go to different gambling forums and then reintroduce yourself before gaining some gamblers to sign under you.
What I think is affiliate marketing only work for content creator i.e. someone who don't care with privacy.
While we're in this forum are pseudonymous, although people can know the credibility and trustworthy someone's account, but it's not enough to reach "whales" and "addicts" to sign under your referral and gamble a lot.
To be frank, affiliate marketing in gambling niche might be the hardest to success except you don't mind to "scam" them i.e. gambling is a way to make money, I can get rich from gambling etc.
Well, it doesn't only work for influencers and content creators, but it is easier for them because they have a large audience and they can easily get a few people using their affiliate links to either sign up or buy a product that is being advertised, even if it's about gambling or a casino, they will get some referrals if they include the link in the description of their videos or live streams. A normal person doesn't have this privilege which is why it's difficult for them.
This is the biggest reason why most people don't get success in affiliate marketing and they stop after doing it for a while because it's not easy to find leads, and then convert them into referrals or sales if you are not an influencer or a content creator and don't have a platform with a large audience that likes you.