Wide Gamut vs Narrow Gamut

A wider color gamut means the TV can display a greater variety of colors, resulting in a more vibrant and realistic picture. LG TVs often offer different Color Gamut options like “Auto,” “Wide,” and “Extended,” under th

Advanced Controls: This section contains more advanced settings like dynamic contrast, dynamic color, color gamut, and gamma. These settings can fine-tune the picture quality, but they can also introduce unwanted artifacts if not used carefully.

I've always understood it that for the 2016 LG sets Color Gamut should be set to standard. This quote says LG told him that in "HDR Bright Room" it's set to wide by default and shouldn't be changed as DC (Dynamic Contrast?) is set to

Note that consumer content does not include colors outside of the Standard Gamut, so a display with a wider Color Gamut cannot show colors that aren't in the original and will only produce inaccurate exaggerated on-screen colors.

Wide would only work if you knew 100% that your content was in the wider native color space of the TV. HD/4K standard dynamic range content is always in the narrower rec709, though.

E.g. if you are viewing SDR HD video, and you have the TV set to Native (which is the wider HDR colour gamut) the video colours get mapped onto the wider gamut, resulting in colours that appear more saturated than intended.

Learn more about the differences between SDR and HDR here. With compatible video, a wider color gamut than the standard Rec. 709 color space, used in SDR content, offers a very noticeable difference.