However, for a lot of film shot pre-2010, grain is an artifact that's not there by choice or artistically. Other than perhaps the film 300.
It just so happens that most of my personal media fits in that box of being pre-2010 which is why I generally denoise.
Something like 30 rock, or The Office, for example, don't have film grain because of some artistic choice.
Interestingly, though, "That 70s' show" does in a few cases even though it's somewhat noisy be default. That's a more tough call.
However, for a bunch of film and especially tv shows, the choice had FAR less to do with aesthetics and was more related to cost. Big budget films certainly could pick any sort of equipment/stock they wanted. Lower budget productions didn't necessarily have that luxury.
I'm not saying it didn't happen, rather that the choice in stock was more often than not "cheap while being as clear as we can afford".
Again, you see this with modern film where grain is almost never added (except for specific scenes trying to give more of a dated effect). That, to me, says cinematographers aren't generally trying to pick their stock to add grain. Some do, but that's the exception and not the rule.
People today miss the point that things like grain can be an intentional directorial choice and not an artifact to be removed.
Sure, for the typical Hollywood blockbuster it has not much value and can break the immersion, but for everything else grain can make you look on a picture, rather than into it. This could be the difference between looking through a window and looking at a painting for example. Additionally grain can emphasize the passing of time. A shot of a still life without grain is something different from the very same shot with grain.
Today it is just another tool in the aesthetical toolbox. And someone somewhere decides when to have it and when not to have it.