That's exactly what happened to me. I was using the disk to install TurboTax & it was taking forever. I finally gave up, stopped the installation & downloaded TurboTax from the website. I just figured it was a problem with my disk drive or the disk itself. Having read your experience, I think Big Sur caused the problem.
And the issues continue now that I have TurboTax installed. Sometimes the program opens normally & other times it takes 6-10 minutes or doesn't open at all.
