Please watch this video before you read the rest, https://www.youtube.com/watch?v=R634ytgt7fw
Personally, for the longest time (even now) games just give me all the sense of accomplishment and feedback I needed. That isn’t to say I didn’t WANT to be productive and do other things, but I COULDN’T. Most things didn’t stimulate me enough or I couldn’t focus on something or bring myself to be productive. If your son is 19 I have to at least assume that you didn’t grow up in a time with as much stimulation around you in the way that this type of things does. If you can’t empathize that’s fine. Think of it like everything else feels discouraging. And even moreso if your son struggles to focus but wants to, everything else just feels BAD.
Get your son on the right medication and dietary changes and work on finding something productive that he enjoys. For me, I think it will be programming. It helps if you find a very diverse and versatile subject. Honestly, look through that girl’s channel if you still have trouble empathizing. Just know that it’s not necessarily a “choice”.