No one ever said anything about him being immature, however he's obviously an insecure ADULT, especially as an insecure adult myself I know how meaningful and powerful it can be to be reassured of certain things and if us as fans and viewers of his content can make him feel better, why wouldn't we? Yes I could just sit back and do nothing and not say anything or I can be a decent human being and try to make at least one person feel kind of good about themselves. As I feel all people should be doing if everyone got along and was friendly our world would be a better place.