He has no responsibility to his followers in terms of any promotion and it should be Ronaldo or his agent who studies the impact of the work they take on. A footballer or influencer has no responsibility in the event that their followers suffer losses, so the followers themselves must verify the truth before participating. Binance is a large exchange and of course they will look for influencers who have the largest followers on social media to promote the products they have.
Their followers are responsible for what they did and what endings they have, profit or loss. It is more easily and comfortable if their endings are profitable. Oppositely, it is more serious if their endings are serious losses.
Influencers are not free of attributed responsibility from their promotion. They can not say they are free to advertise anything, any brand that comes and knocks their doors. They simply advertise these stuffs, receive money and enjoy their life without any responsibility. It's not true and I hope you actually understand what you said here.
It's like black and white on how laws, regulations are used but in both laws and moral, influencers are not responsibility-free.