A further update on all this... from: https://www.zdnet.com/article/adobe-to-block-flash-content-from-running-on-january-12-2021/
"Adobe has released on Tuesday the last update ever for its iconic Flash Player app, which the company plans to retire at the end of the year. ... Skipping this last Flash update won't remove this "time bomb," however. Adobe told ZDNet that the killswitch code was added months before in previous releases and that this last Flash update only modifies the language used in the prompt that will ask users to uninstall the app."
That pretty much seals the fate of Flash. A user attempting to bypass the kill switch by installing an old Flash version (assuming they can even figure out and find a version prior to the kill-switch introduction) will only result in them using a Flash version with known security holes - the older the version, the more holes.