There are a whole lot of landscape photographs out there I can vouch for their realism 1% of the time because I do a lot of landscape photography myself and tend to get out at dawn and dusk a lot. There are lots of shots I got where the sky looked a certain way for a grand total of 2 minutes before sunrise, and I can see similar lighting in other peoples' shots as real.

A lot of armchair critics on the internet who only go out to their local park at high noon will say they look fake but they're not.

There are other elements I can spot realism where the armchair critic will call it a "bad photoshop". For example, a moon close to the horizon usually looks jagged and squashed due to atmospheric effects. That's the sign of a real moon. If it looks perfectly round and white at the horizon, I would call it a fake.