The only video I've seen that uses the YouTube subtitle capabilities to their fullest, with animated subs etc is this one https://www.youtube.com/watch?v=MDc1mjrIsPM and even then you have to dig down into the settings cog and choose "English - Animated" manually
https://caption.plus/ does excellent work for a couple YouTube/Nebula channels - not as exciting as the above, but they do coloured speakers, positioning to avoid in-video text, and an occasional animation to punch up a joke! I'm most familiar with their work for Tom Scott (+ the Technical Difficulties) and Jet Lag: The Game.
