In modern tech circles, the utilitarian mindset is going strong, now that the hacker ethos is dead and it’s all about being corporate friendly and hireable.
It's always easy to complain about others not being generous enough with their time, but we always have an excuse for why we won't do it ourselves.
You can't, at least not if you want an acceptable result.
In photography, if you have a JPEG photo only, you can't do post-facto adjustments of the white balance, for that you need RAW - too much information has been lost during compression.
For movies it's just the same. To achieve something that actually looks good with a LUT (that's the fancy way for re-coloring, aka color grading), you need access to the uncompressed scans, as early in the processing pipeline as you can get (i.e. before any kind of filter is applied).
Honestly, by weakening copyright protections. People who love the works will do the work to protect them when they don't have to fear being sued into bankruptcy for trying to preserve their own culture.
There's a fucking lot of things that are not worth it monetarily, but worth it for the sake of itself. Because it's a nice gesture. Or because it just makes people happy. Not to sound like some hippie idealist, but it's just so frustrating that everything has to be commoditized.