i think the comparison to Waterworld is pretty fair comparison. It's not necessarily a bad thing. Where Jim is wrong though is that Waterworld didn't really do anything new; like, Waterworld was a pretty dull movie, not a bad one, but it introduced almost nothing new to films... "The Kevin Costner Epic" was such a trope at that point, too.
If he said Shenmue is like The Postman, then them be fighting words.
Shenmue 1 was one of the first games I ever played to make me think that there was actually a world existing outside of my character. I don't think that Shenmue is an especially good game, and I really thought the hype for Shenmue 3 was misplaced because people wanted to root for a console favorite at the time, but that "Feature," that it felt like I was a part of a world, as opposed to me being the central focus of the world, was really unique... It was something that I had never experienced in a game before and, importantly, one that I *always* wanted to experience even as a kid playing NES and Genesis games. As a kid, I always wanted a game where you could do normal things, walk around towns, go into stores, I used to talk about this game phantasy with friends of mine... I actually rented "Bart v. the Space Mutants" on NES because the box art made me think you could do that, and of course you couldn't. It took a long time, ~1999 or 2000, whenever I played Shenmue, for me to feel that in a game.
Even other open world-esque games, like A Link to the Past, it still really felt like "you" were the world. Sure, there's shopkeepers and house maids and what not, but maybe other than a few small exceptions, you only see those characters talk to you... You don't see the shopkeeper going to the beekeeper to buy honey, or any sort of world outside of you walking around in it.
In that respect, Shenmue 1 is similar to The Shining for me. Now, I'm not a movie buff or film guy, but I know the Shining was a movie that did a lot of things *new,* or was "The best first" example of a lot of film concepts. Like the way the big wheel scenes are shot or the aerial footage at the intro, I;m sure film experts or even moderate enthusiasts know the name for this automatically. The Shining is not a good analogy to shenmue because it's a successful movie that is widely, critically and popularly praised (although IIRC, it wasn't universally well received when it launched?). I'm trying to think of another movie that generally isn't *that good* but did a few new things so well, that few other movies had done before, that it's still culturally appreciated years and decades later.