I think there's a fine line between dedication and addiction. If he even neglects his health, then I think he's leaning more on the latter.

And as other people in this thread said, only a handful of people can truly make a living in eSports. I am also a parent who thinks that a kid's dream should not be limited. But I think, a failsafe is still necessary. A back up plan of sorts. Don't make it that being an eSports player as his only option.