I would say that is the #1 modern hobby, above all among men, although I think genders are increasingly balanced now.

The gaming industry shifts more money than film and music combined doesn't it? Whilst that's obviously a very poor capitalist proxy for the time and engagement that the sector occupies in our lives (and also includes a load of Fruit Ninja/Candy Crush type stuff which again doesn't count as a 'hobby'), it does suggest a lot of people dedicating a lot of time to mastering the intricacies of their chosen games.

Where it stands on the 'infidelity prevention' scale is another matter, at least virtually. More than one tab may, perhaps, be open in the mancave...