The first thing that immediately came to mind with his answer to not wanting to expand the Vinesauce brand was "I want to stop streaming sometime soon so what's the point?"
As has been discussed already, the man's getting old. And with age comes contempt for the youth, and having to deal with that kind of demographic on a daily basis is wearing him down more and more. Every passing week you can hear the weariness in his voice increase, even his rare moments of excitement and joy are noticeably toned down from what they used to be, and he generally has this air of confusion and indifference whenever more modern topics are brought up by the chat, such as the latest memes.
Between that and his clear financial stability, he will up and disappear in the not too far off future, retiring in peace. I think the only thing that might keep him around for a while longer is the fact that his fanbase are the only people aware of his music, and once he dips nobody's going to be aware of his band anymore.