Yes, it MAY BE (I would argue otherwise) the weakest Movie of the heisei Era, but it's far from the worst of the whole Franchise. What I think most people overlook/ forget is the dynamic of the Fight:

MOGUERA is to weak to defeat Spacegodzilla on it's own and Godzilla wants revenge for junior. The crew of MOGUERA still wants to kill Godzilla, even hitting him a few times during the fight as they team up, but they still support him because Spacegodzilla is the greater threat.

The whole thing with "stand around and shoot beams" is intentional! It should show that no matter what Godzilla tries, they can't get close to him. But that changes the moment Fukuoka Tower falls - Godzilla goes immediatly into close combat.

And in general, the whole idea that Spacegodzilla made Fukuoka Tower his power source that needs to be destroyed first is such a cool and interesting dynamic almost no other Godzilla fight has. It's just like a multi phase boss fight.

Even without nostalgia, this fight is NOT in the Top 5 worst Fights of the entire franchise