It doesn't mean the Gambling addicts increased, the internet enabled the Gambling more accessible for wider audience and also don't forget the population of the world is increasing day by day so it's not a wonder that the boom happened. Honestly it's late boom since internet became pretty popular in the previous decade itself but it was expensive at that time so only certain class had the previlage but now every got the internet access in their palm and pretty cheap too.
You are Right, as the day goes by, they make it more easier to gamble from the comfort of your home with interesting offers to continually drag people more into wanting to try it out, while iþ feels like it's late boom to you it's simple because people get to embrace it more recently than they have done before and that is probably because now it's becoming simpler with attractive and interesting interface for gambling than it has ever been before now.