Is it certain that having a functioning youtube app is under Roku's control? For all I know, Youtube doesn't want Roku devices to have a functioning youtube app.
My Roku TV has a YouTube app that works perfectly as far as I can tell.
I'd be happy with an HBOMax app that doesn't consistently crash whenever I open it.
I’ve yet to find a platform where the HBO Max app isn’t a total piece of garbage, iOS included.