Those niche people are the developers they want to use their software. When that niche is the target audience for whole product line of yours pleasing them is a good idea.
The historical value is invaluable for our species, especially in the far future. There is a moral imperative for this kind of thing to be made available for posterity that, in my opinion, completely overshadows any commercial, copyright or political correctness concerns.
Frankly, there should be regulations guaranteeing source code release after a few decades, and that all code, including third party code, is released from copyright protection. In return, companies should be granted legal protection from any potential legal consequences. It was over 30 years ago. The idea that somebody should be able to sue Microsoft for copying code or a third party can sue them for releasing it or that they should in any way be punished for unsavory language used THIRTY years ago is clearly utter insanity.
