That's just sad. The level of grind it takes to become pro is nuts. For every one professional player or streamer there's a countless number of people that have wasted their lives on this stuff.
The scale is such that to be good it's very often a case of mastering a zero-sum game. Rote repetition until it becomes [hand] muscle memory. The same shit, over and over, until your eyes bleed.
Aged nine and up? Just let the kids have fun. High-level e-Sports should be considered child abuse at that age.