Exporting Video in a Color Managed System Yields a Thin Video file in External Players

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First, if you reimport the file into Premiere, does it match the original sequence? If so, the problem might not actually be ... Premiere.

We need to know the OS, the media, including color space, and any details about your monitor setup and possible calibration.

Because it depends on what color management is being used for the display, doesn't it? For example, Mac's, set to "Rec.709", apply a display transform of 1.96. This is actually, by the specs, the camera transform. That ... is not correct  display CM. 

While, if available on your Mac, using the "HDTV" setting rather than the Rec.709 one, will cause ColorSync to use the actual broadcast gamma 2.4 for displaying video files. The correct Rec.709 display color management.

So depending on the color management choices made by a Mac user, you might get two different looking images from the same file ... depending on which CM choice you make.

Premiere presumes the straight broadcast spec, using the broadcast-use gamma of 2.4 by default. All colorists I know, when setting up their incredibly complex color management, use gamma 2.4 for broadcast spec use. No matter what OS the computer is. And they are furious at Apple over the problem, as most of them are Mac geeks, really.

Users can now select the gamma used by the Program monitor in Premiere 2024, the 24.x builds. That's in the Lumetri color panel, Setting tab, under Project/Viewer Gamma. Three options, the 'correct' gamma 2.4 (broadcast), gamma 2.2 (web use), and gamma 1.96 (QuickTime) ... the latter is for use on a Mac, for Mac only exports. (As, if you get this looking as you expect on your Mac, it will be way too dark on any full-on broadcast spec viewing system.)

But ... it seems you must also use the preference option for Display Color Mangement, and probably ... the Extended Dynamic Range when available option.

Supposedly, if using the Preferences DCM option, and selecting the other things, you should get very similar views within Premiere and using the QuickTime player on a Mac. If you aren't, then that is showing something isn't working correctly. And would need fixing.

VLC will probably show a much darker image in the shadows, similar to viewing on a broadcast spec system.

Further, some people unfortunately override the normal display settings of either the OS or the video card or the monitor, and specify that Rec.709 should be seen as "full" range. Which is based on a complete misunderstanding of what full and legal/limited are. They refer to the encoding math used in the file, not to the dynamic range of the file. The dynamic range is the same, just encoded differently.

All YUV (technically Y-Cb/Cr) media should be set to "limited" range, and all RGB media should be set to full. And that latter is only the massive 12-bit full-on RGB space files, and if you don't know what that is, don't use it.

In a properly setup system, both YUV and RGB files will be displayed 'full' ... but if you set limited to show as full, any actual RGB files you use will have totally crushed blacks. And your media will not look as expected on broadcast compliant systems either.