Most astronomical images (even those taken in the optical) are not as a human eye would see/perceive the scene. They're almost always made in a way to highlight features of scientific interest, look aesthetic, or both. And in the case of images outside the visual spectrum, they are assigned representative colors.
Another angle is that astronomical images are generally intensity images, taken through a single filter, rather than inherently color images. Several of these images, taken through different filters, can be combined to make a color image. However, even if taken in the visual portion of the spectrum, the responses of the filters generally won't match the human eye's responses, so the images aren't what the human eye would see.
For example, the Spitzer Space Telescope (covering 3.6-160 microns), captured images of astrophysical objects and these images were used to generate representative images:
- Helix nebula https://en.wikipedia.org/wiki/File:Comets_Kick_up_Dust_in_He...
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- Cepheus B and C https://en.wikipedia.org/wiki/File:PIA23126-CepheusC%26Bregi...
JWST operates largely in the infrared (though it has some overlap with the visual range), but will undoubtedly capture wonderful images in the infrared and these images will be combined to make stunning pseudo-color images.