No not really provided that you do it to the right audience

Your audience should be a group of sensible and responsible adults who can make their own decisions of course we are talking about morals and ethics but if we talk about it legally then it would be different since it would mostly depend on your country's rules and regulations. Going back to morals and ethics, I think promoting gambling is not necessarily a bad thing as long as you are not promoting scams fully knowing that what you are promoting is indeed a scam and would put your audience to harm