Interesting post OP. You certainly see some creative works out there that admittedly look more like an artists rendering than a photograph. I’ll take a stab at an answer to your question...
The true color of light corresponds to the wavelength of the emitted light. Different types of ionized gases have their telltale signature wavelengths and color, hydrogen alpha, oxygen III, sulphur II, etc. so theoretically, if you had a uniformly sensitive color sensor (does such a thing exist? Trick question) you would arguably be capturing the true color in the right amounts of each. However, there are several hiccups, the primary being that color sensors, or more to the point Bayer matrices on top of greyscale sensors, are NOT uniformly sensitive and tend to favor one color more than others. Another issue that may change the received color versus the transmitted color is red/blue shifting that shifts the wavelength of light we receive one way or the other depending on whether the object is moving away or towards us. Another issue is that deep space objects that are exceptionally far away and faint, require us to go deeper and longer to, for example, bring out the reddish nebulously in the spiral arms of Andromeda.
Narrowband and LRGB imagers address these shortcomings by isolating wavelengths or band passes to maximize data and then the imager constructs a final image balancing the contribution of various wavelengths to the final image and sometimes mapping it to, for example, the Hubble palette. These tend to show much more detail and are of more scientific interest, but faint hydrogen alpha may be leveled up to create a more pleasing image that may not correspond to comparative levels in relation to oxygen III, for example. Sometimes these images get a little too artistic looking for my taste than photographs, depending on the skill or taste of the processor of course.
If you could get over the color matrix issues of OSC and capture color uniformly, this would theoretically present the true balance of colors and likely be more representative of the true color of an object.
Edited by WoodlandsAstronomer, 01 December 2020 - 07:43 AM.