Dorothy, thanks for posting this notice again as it probably warrants reiterating. Yes, it is indeed an unfortunate decision Polaroid has made.
A few months ago, I during a Google search on SX-70 film, I stumbled upon the Judge's written decision in the Polaroid vs Kodak patent infringement case. I didn't read all of the document due to its length, but the first 100-some pages were a fascinating review of all the business and technical issues that went into bringing the SX-70 camera and film to market. According to testimony given by the most senior Polaroid executives, including Dr. Land, the SX-70 line never was very profitable despite its seeming popularity. That was the reason for the camera's rather short production life despite its acclaim.
Given that the film line was seldom profitable too, I believe Polaroid deserves credit for keeping it in production as many years as they did. As an engineer, I would bet the obsolete components necessary to keep the production line running could be replaced, but, there comes a time when a company has to make a decision such as they were faced with, and they have sadly made it.
I'm hoping I can buy up several boxes of SX-70 early next year so I can enjoy it just a little while longer.