@Don't I did a report on him back in elementary school. So I've always had in my mind an idea of what his motives were. The Liberty's Kids series actually featured a portrayal of him that didn't paint him as a supervillain.
YouTubers have every right to delete overly negative comments on their videos. It does not make them seem petty whatsoever. If they weren't supposed to do it, then why would YouTube give them the capability to do so?
(Note: I could have sworn I'd already posted this here, but I did a search and couldn't find anything.)