If you need color accuracy then you're calibrating your monitor hardware.
People using Macs certainly do care about ColorSync. That’s the name of the software which uses the display characterization to keep colors looking as expected throughout the operating system and most applications.
Using LUTs either at the application or OS level to adjust colour information is a big no-no, although that doesn't stop some people from doing it. You simply don't want to change your colour space[1] until you absolutely have to.
The point of calibrating your monitor (which is a hardware + firmware level problem) is to see how your RGB image will look on a colour space restricted piece of hardware (for example in video this is often 12-bit RGB --> Rec709).
Same story if you want to show your image on a display with a different gamut.
Most gamut mapping algorithms used in practice (whether on a display or in software) are actually pretty mediocre in my opinion. It would be possible to do substantially better by writing your own code, at the expense of being a bunch of work. Alas.
P.S. The Wikipedia article about color space (and articles about many other color-related topics) is pretty terrible, but I’ve been too lazy to rewrite it.
