I wouldn't knock those who've had the chance to see Wrath of Khan on film. As someone who has the opportunity to see it, I too can attest that the coloring on the Blu-ray matches what I saw on screen. I could tell just by the first shot of the film on the Enterprise bridge. Sorry I can't produce concrete evidence, since they don't allow you to photograph or take video of the screen. Some video transfers can't always be trusted and you can't judge a film squarely off of your experience with previous versions. I've seen a video version of Star Trek: The Motion Picture that was unbearably dark that I could barely see anything, but that's not the case with the Blu-ray edition. Another example is how I recently seen a film print of The Terminator and the color from it matched the newly remastered edition than the first Blu-ray edition.
Do you know
that The Terminator was actually being shown from a film print? Because like has been said, modern cinemas are kitted out with digital projection, and that involves downloading an file (no doubt sourced from Blu Ray or other high definition equivalent) and it's all done on computers. Chances are if it was a recent screening of The Terminator, then it basically was
the Blu Ray.
If you're viewing of TWOK was likewise a recent-ish one, then chances are there's a very good reason
why it matches the Blu-Ray in terms of coloring...
Almost no theaters show film prints anymore. I should know, I was a projectionist for nine years until the new technology got good enough for everything to be changed over. If you're watching any movie in a theater now, trust me, you're not
seeing a film print.