I think Holmes was so overwhelmingly, pathetically, intent on just slobbering all over the movie (and being unable to restrain his excitement at being able to talk about it), that even having Simmons there simply to say "Jesus, it wasn't THAT good." would have been an improvement. I don't know if Lathan asked to have Holmes on to pair with him this episode, but there were multiple times in the last third of the episode where he felt compelled to cut Holmes off with a declaratory "Huh" and then change topics. Not even a "That's interesting!" just a "Ok, you have to stop your bullshit now it's embarrassing." He tries to sugar coat it at first (when Holmes reveals his abject ignorance by implying Titanic launched James Cameron's career), but near the end even he gave up.I think that's it--which I think does support the point. He doesn't like superhero movies, that's fine, but he doesn't seem to be someone who could add a lot of nuance to a discussion of superhero movies.
Maybe the issue isn't the need for Simmons so much as Holmes was the worst movie podcast co-host I think I've ever heard.