It's not high standard.
Scenarios similar to our world, with an Earth, Moon, and Sun, are assumed to be standard.
But isn't HH literally that the case? Hell isn't Earth, Heaven isn't the Moon.
Of course, the Earth, Moon, and Sun in HH will obviously be assumed to be the same size as in real life because it's a scenario similar to real life.
But in the case of Hell and Heaven, we're literally talking about another supernatural dimension with supernatural celestial bodies. Like, why should we assume it's similar?
And especially why does it have to be Earth? Planetary size.
As Tllmbrg said, Heaven looks like a moon, so why don't we simply assume Heaven is a moon instead of a planet?