The World Health Organization(WHO) is about to recognize gaming addiction;asa mental health condition it is called "Gaming Disorder". The WHO defines gaming disorder as a recurring or persistent behavior pattern that is severe enough to affect crucial and important aspects of life. Examples would include gaming taking priority over eating , sleeping or other primary and necessary functions..
For me it's true, the excessive playing of various online games affect to the children's important activities. But your child will not be affected by gaming disorder if you discipline them. Give the time when they can use gadgets and play games.
Well gaming addiction is common though and yes it is a disorder or a disease , by the excessive gaming it can positively cause an negative effects mostly on the behavior itself, and to be honest this is my title of my research that it could positively affect.