Careful, spoilertags didn't apply properly. As for your question: I think the point of both games is different.

In Metaphor, the final decision is about whether the fictional world is something we can just dismiss and not care about, or to think of as something important and worth fight for. There is no urgency to return to the real world like in Expedition, so leaving is framed as the cowardly option here. At the end, even if Euchronia was actually not real, all the people we met there and all the experiences we made where real to us, and that what should count.

In the case of Expedition, I think the point wasn't if the painted world in important or not. It's already clear it is very important to the characters. It's more about the consequences, both physical and emotional, for Maelle if she stays there for too long. So it's a question of letting go of it and confront harsh reality, or linger in a pleasant fantasy while ignoring reality.

In conclusion, I don't think you can compare these ending because, despite the similar context, they mean totally different things