Can government control the internet, can they sanitize everything that comes to the people through the internet, ads and other means are not targeted on gamblers to get addicted, people use them to abuse every opportunity in them just to satisfy their own personal desires, are these same organizations not being regulated by government agencies and yet they make their promotional campaigns through various platforms to spread the news about their website, yet so many abused it, who are to be blamed in this.
Well, though governments and telecommunication authorities can filter the internet or what people can use or see on the internet, they won't be doing that if gambling is not illegal in a country and they might just try to spread awareness about responsible gambling but they won't be forcing anything on people since it is legal and allowed within the country. It's a different thing if gambling is illegal and people are not allowed to get involved in it which is when they will ban ads or gambling-related platforms within the country.
Also as you said, gambling ads are not specifically targeted at people to make them addicted to gambling but they are merely to run the casino since casinos are businesses for their owners and every business is allowed to promote their products and services to run their businesses and earn revenue through them.