You can tell they are leaning into the fact that we don't care about the humans and likely cut out a decent amount of that content. They still had the challenge of structuring it with the humans split into "Team Godzilla" and "Team Kong" factions. But they could have still cut that down a bit by getting rid of a few characters...

Speaking of the factions, I find it interesting that the two sides never really met each other or interacted - so neither side ever knew the full story. Team Kong had to have been like wtf?!?! when they saw MechaGodzilla come out of nowhere. Team Godzilla on the other hand didn't know anything about Hollow Earth and the Kong homeworld...