I work in the games industry, specifically eSports - we make probably the biggest title for competitive eSports at the moment, so I have *some* insight into it, but I wouldn't consider myself an expert on gaming addiction. But I obviously mix with people from all the big games studios, so I do learn a lot.
Personally I think gaming addiction has gotten worse over the years, but probably because it's a numbers game; more and more people are playing, combined with the fact that the games are designed to be fun and create quite a buzz when you win.
I think ranks and progression drive obsessive behaviour, large numbers of people take their ranks REALLY seriously. I know this from playing lots of CS and Overwatch - rank means everything to a lot of people, and they becoming obsessive about continuously ranking up. The way the ranking systems work is designed to always match-make players of a particular skill level together, so few people tend to improve much above their seeded skill level, so they embark on this quest to play and play and play and play. Unfortunately unless you're playing against people who are much better than you, you never really improve much. This is mainly because the system wants to provide you with a fun experience, rather than matching you with people who are 10x better than you, but the tradeoff is that you don't learn anything, some people do - but most stay within their seeded ranks.
An interesting trade-off of this, is the incredibly lucrative 'boosted accounts' business, where very high level players create new accounts from scratch, play their seeded matches then sell that new highly ranked account for $hundreds. A lot of 'pro players' are doing this to make money, but it does allow others to buy those accounts, and get seeded against much better players, and it's a very common problem in eSports but quite a fast way to improve, if you can hack it.
I think buying loot boxes for money is problematic, China created laws which force us to publish the drop rates of certain loot - which I don't disagree with, but then again china is pretty mental with the stuff we have to do for them.