If you are popular in social media and have a facebook page / YouTube channel, Affiliate Programs can give you a good easy income. The more the followers you have, the more easily they will join with your Affiliate link and you will get nice passive income.
It depends on what kind of social influencer you are. In the social media world, there are different types of influencer, gaming, beauty products, gambling, etc. Now if you are a gambling influencer surely that you can be good at any casino affiliate programs but if you are on a different type then your followers won't even try to click the link that you are advertising or worst they might unsubscribe to you.
This is a good way you can get more profit from which I tried it, to whom the phrases you explain to users must be compelling in order to enter the link and offer them the advantages, especially if you own a YouTube channel and many followers
Social media marketing is the only way to truly popularize any referral or affiliate programs you might be able to use, there's basically no other way to effectively compel users to get involved without targeting an insanely wide audience through the power of Facebook, Twitter, Instagram, etc. It's way easier to reliably earn money if you actually have a website sponsor you to promote them outside of affiliate links, but that only comes if you have a big and dedicated following for your "brand". YouTube feels like it's become a lot more of a "swing and a miss" these days, since they're ready to shut your account down for basically anything.
As for casinos with affiliate programs, Stake has one. As far as I'm aware, and as it's been said multiple times before me in this thread, it is reliable and one of the better options that exist.
if you think Youtube can shut your account for literally anything , try Facebook
they are even worse in this regard , highly ... uhm , politically correct in a bad way , when you can get banned for saying something that may be considered offensive
or posting a video that their algorithm will deem inappropriate even if it is your birthday party ( and yes , it happened to a friend of mine )
Youtube is not the same as before , too many advertisers stopped working with the platform and Youtube bloggers are earning less
it is still a very good tool to do affiliate marketing , with the right video and the title one can get lots of affiliate signing up
if you want a good example, google Mike The Mug's videos , this guy does i every time - he has hundreds of signups under his affiliate
and some of his videos have 500.000 views and more