If you're committed enough to slog through an hour of a nonsense, boring, overly complicated plot that progresses solely on stupid actions by unlikable and forgettable characters that deliver lines like it's a high school play (with the exception of the criminally underused Charles Dance), you might get rewarded with some serviceable monster-on-monster violence, that can be downright great when it isn't jarring and confusing. I understand the whole "It's a Godzilla movie! It's not SUPPOSED to have a good plot/acting!" mindset, and I fell into that trap, too. There is a point where it starts to matter when considering if you wasted your time or money, and Godzilla: King of the Monsters reaches that point about 45 minutes in, when there haven't even been two monsters on screen simultaneously, yet. King of the Monsters would have been much more palatable if it didn't even have a plot at all, and opened cold cut to monsters punching each other in the face for 2 hours, and then the credits roll. If you want a genuinely well-written Godzilla movie that also has good action sequences, I recommend renting 2016's Shin Godzilla. If what you want is to see spectacular monster fights and don't care much about plot, rather than wasting your hard earned money on this tragedy of a movie, I recommend:
A.) Renting Kong: Skull Island if you haven't seen it yet.
B.) Watching the animated Godzilla movies on Netflix, if you have Netflix.
C.) Waiting until all of the monster fights from King of the Monsters get posted to YouTube and just watch those.
EDIT: To specify on the complexity of the plot. The plot itself isn't that complex, but the character motivations are all over the place that it's really hard to follow what any one faction is trying to do. At one point I was pretty sure every group wanted to kill all the monsters, but then they all changed their minds.