Everyone always thinks the ocean is super deep from the beach outward. This is not the case. Just because a boat will float seemingly close to shore doesnt mean the hull is way down in the water
An aircraft carrier only has a draft of some 12 meters. Godzilla is over 100m. Much of the North Sea is only like 40m deep, with shallows much less than that.
I mean he clearly just walks out of the water in the movies, he’s not suddenly coming up, like you clearly see him slowly get higher and higher out of the water as he gets closer to shore. Also the ocean isn’t that deep close to shore.