This made me think on a tangent, on whether divulging spoilers for an interactive experience have a heavier "stigma" than for books or movies. Five or 10 years from now, or even a month from now, I can't imagine being offended if someone were to spoil who dies in "Avengers: Infinity War", or the 3rd season of GoT. Whereas a video game is much more inherently about the "journey" -- e.g. you have to do some work to get to the end. I think I'd be annoyed if people were just spoiling "The Last of Us" 10 years after its release (which is likely to be after its sequel is released).
That said, I don't think I'll ever find time to play the original Shenmue. But hearing more details about why it has cultivated such a fond following makes me very interested in playing its Kickstarted sequel.
Unlike other mediums, the number of people who play games has grown exponentially over those 20 years.
I think it's safe to say that the vast majority of people who play games now have never experienced Shenmue even though it was a blockbuster title on the 9 million Dreamcasts that shipped worldwide.
And you're not only spoiling the 20 year old version, you're also spoiling the HD remaster that can be bought right now on PC.