I'm not going to argue against having a star of a truly classic movie talk about it but in my listening experience, those type of commentaries simply turn into the person repeatedly saying how great all their co-workers were, narrating what's happening onscreen and telling the same stories that...
And the new one that was on the Blu-ray was fan made.
I'd be curious what the last time a studio made a legitimate documentary for a catalog title. I bet it's been way more than a decade.
You really expected a documentary in 2020? Twenty years ago, sure but studios don't really make new special features anymore especially for catalog titles.