In astrophotography there's (almost) no such thing as "natural". It's definitely an aesthetic, but it's based on "real" data.
Also, in the case of this specific image, I think it's important to note just how deep the images are - they're processed for high resolution in the individual components, so the mosaic has an absolutely huge resolution. When downscaled to look at the whole thing zoomed out, that might give some of the impression of over-sharpness.