That's...a good question. I rarely think of the media of a world I create, so that's a good thing to consider. It really wouldn't make sense that a world in which something fantastical happens, said fantastical event is never portrayed in their media. But I think humans would fantasize about giant robots in any universe, or have modern media portrayals of monsters outside of mythology. I will say that an Ultraman-like story might be specific enough as to be feasibly not represented in this world.

So I'll say this, yes, kaiju and mecha genres exist, but a specifically Ultraman-style story/franchise doesn't.