[Lio]

I may be misunderstanding this but isn't the point in Inception that what they are experiencing is explicitly not real?

That because they are inside a dream-like state the rules of reality can be broken and it is only by spotting when the rules of reality are broken that you can tell you're not in the real world.

[Retric]

That I don't have a problem with. You can have people see all kinds of crap while tripping on LSD without issue.

It's the mechanics like 10^(layers deep) where going deeper kept increasing time compression in dreams. Dragon Ball Z for example had space ships, but the mechanics of the world where based on fantasy ideas.