This is only from my experience and my children, so anecdata at its best.
Gaming on the whole has been a positive thing for my boys. They are now 10 and 11, and play collaboratively on games like Minecraft, Tales of Zestiria, Thingummy and the White Witch (can't remember the exact title). This year once the youngest reached 10 I have allowed them to play Minecraft on servers but up until now it's been offline / no chat rooms / no online contacts at all. Online Minecraft they have to have the chat channel off and they aren't allowed to accept friend requests.
They are learning to code (started with scratch and now on to JavaScript), they have amazing hand eye coordination, they have very good logical and deductive reasoning skills, they still seem to be imaginative in terms of their writing / penspiration at school. They are both natural mathematicians and this seems to have improved since they started coding and gaming.
They regulate their own screen time in as much as it has to be earned. Some jobs are expected (keeping bedroom tidy, feeding animals) but some jobs are paid for in screen time minutes (dishwasher, laundry sorting, collecting and sorting the eggs for example). Each job gets 5 minutes (or more depending on the job - washing both cars gets 30). They also get 10 minutes for every hour's exercise class they do and if they do 3 classes and one sparring, they get it doubled as a bonus (or 5 classes if no sparring classes running). Sparring tends to be on Friday afternoon so they get their bonus in time for the weekend.
There is a limit of 2h per day and homework / chores / anything else I deem necessary has to be done before they can spend their minutes. They start a timer when they turn the computer or console on, and when their time is up, they turn the computers off again.
I have noticed that my younger son's behaviour is more difficult after he has been playing computer games - more sulky, prone to tantrums, everything is in the too-hard basket and he's far more easily wound up by his brother. We are working on this, every time his attitude goes too far he gets a screen time ban of 24-72h (depending on how bad) and he has to find something else to do in his free time. Typically it'll be playing a card game or board game if he can persuade someone to play with him, or reading if he can't. He doesn't seem to be able to entertain himself without some kind of external input (screen or book or game with others - he won't play lego on his own, for example, or sit and do a jigsaw or anything arty) - but this was his personality before we introduced screens into his life, he's always needed some kind of external stimulation. He doesn't have any problems with turning the screens off once he has spent all his minutes - he's always been really conscientious about setting his timer and turning everything off when it runs out.
My older one seems to be the same whether he's had screen time or not. No tantrums, no sulks, no issues with keeping himself busy with something else (lego, arts, reading, making up stories - he's currently writing his own Pathfinder module) - I think it's just his personality type.
We are a gaming family though - DH and I met online in EverQuest (Antonius Bayle server for any other gamers out there!), and we regularly play Pathfinder (D&D roleplay) as a family which keeps their imaginations fired. They have a pretty well rounded life, with lots of outdoors stuff as well as indoors.