Moonfall: B
Roland Emmerich movies are almost always ridiculous extravaganzas. Most of them are ludicrous enough and/or dumb enough to break my suspension of disbelief right away, so I'm not a fan in general. 2012 is an outlier for me: it's definitely ridiculous but it's also interesting, engaging, and compelling enough to be entertaining rather than annoying.
Moonfall is my new second-favorite Emmerich movie, after 2012. There are a lot of similar themes. 2012 is an all-out disaster extravaganza while Moonfall scales back the disaster screen-time in favor of expanded space and moon scenes and a more involved story. One big difference is that 2012 has better acting, with the portrayals of many of the main characters in Moonfall seeming fairly stilted.
All in all it's a ridiculous, interesting, and fun action/sci-fi/disaster movie.