The pro players in esports play for hours a day. Now i know what you are thinking that is really unhealthy and it can’t be considered a sport there is no physical activity. The definition of a sport is an activity that requires a high level of concentration. The word physical is not in that definition.
There is a lot of concentration that is involved in video games I know because I have had experience not with pro gaming but just playing in general. When I play i want to do my best so I put all my focus on the game. When the pro players play competitively they need to do there best