At least thousands of Trebek episodes still circulate today, and there's a legitimate possibility of them being rerun on a Pluto-type channel in the future. Since I was old enough to recognize (around the late '80s), I've probably watched approximately three-fourths of all episodes of Jeopardy! when it was running. Sure, there are those categories (like European Literature) that I will never perform well in, but its still a great learning experience that is still valid when watching old shows. I was always curious in checking out how much Art Fleming circulates, but given the unfortunate circumstances of most episodes being wiped, we'll never get the luxury of seeing how good that version was.
It will be interesting how much of a retool Mike Richards want to the show now that an important era of the show's history has passed, from the theme, set, and if the ratings sag, any other intangibles.