Online gambling just made gambling easier and more accessible than visiting physical shops, I don't know of oys right to say that it leads to gambling addiction because more people having access to gambling in an easier and flexible fashion does not not amount to gambling addiction. Although it has the tendency of making people gamble beyond limits since the deposit method is easy and smooth but I don't believe it leads to gambling addiction.
I also think that with the increasing ease of access to gambling platforms, it will not actually increase gambling addiction, because it comes back to gamblers how they can manage their gambling habits. Because if the person really can't control themselves, then whether it's online or offline gambling, they will easily become addicted to gambling. The point is, never blame online gambling for making it easier for people to gamble, but blame the gamblers who play and become addicted because of it.