I don't think any addiction is "healthy" really, but I wonder if we are all addicted to something, if there are better and worse forms. ... too much of anything though.
Well at the most principle level, you could be basically asking/telling/wanting them to sacrifice their mental health/time with important relationships/etc "for the greater good".
Absolutely! but if someone's loved one was dying of cancer and this person might have the cure - do they want them to go on holiday or spend their time gaming? Makes for an interesting ethical dilemma under certain conditions.
Are they then "selfish and irresponsible" if they choose to prioritise their mental health or time spent with their family over curing cancer
Look how athletes have been treated in this regard recently. And they are playing sport....
I don't think I've consciously thought of that as an addiction before.
I find people are addicted to their thinking too - where they keep thinking in loops, rather than seeing if there is another thought they can have. I suspect it has something to do with how they identify and thinking something else - doing something else - means losing who they know themselves to be. But, if they don't try, what do they really know about themselves?