The McDonald's lady's case blew up because the jury slapped McDonald's with huge punitive damages. If she would have gotten the 10-30k she asked for initially or even just the 125k for actual damages no one would care about the case. But the 2.7 million in punitive damages just make this lawsuit seem frivolous. But she had no control over that.
And IIRC one big reason why she won was because the cups weren't suited for holding such hot liquid. The temperature of coffee didn't decrease in McDonald's after the lawsuit.
Because it's often not worth the investment. You would pay a shit ton for a one time conversion of data that is still accessible.
If the software became open source, because the company abandoned it, then that cost could potentially be brought down significantly.
You are also missing the parts where functional hardware loses support. Which is even worse in my opinion.