I'm pretty sure they revolutionized the idea of special features such as commentary tracks, behind the scenes footage, etc., but were they the first to do it? Was there any other distributor that put so much care into the entire home video package like Criterion in the 80s and 90s?

Pretty much, but you have to consider that since LD was Multi-Audio to begin with Criterion was really just fulfilling the promise of the format when most publishers wouldn’t consider the expense. They weren’t in a position to innovate anything that wasn’t already built into the format and demoed by Leonard Nimoy in the Magnavision promo.

Criterion were the first to make spending money on special features a normal thing. Their main goal in the beginning was just putting out movies period and making things available that could normally only been seen in very limited engagements at very few theaters. Realizing that meant their movies would cost more I think they considered it an obligation to make the releases as good as possible. It was $150 for some of these things, which is a lot of money for movies almost nobody wanted to see. They made sure you had a good cover and the transfer wasn’t too messed up and if it was a release that would pay for itself and worthy bonus material could be found or created they’d try to include it.