Thanks for the suggestion, Tim. I saw that somewhere (and it may have been your post), however IE is no longer available as an optional feature (after June 15, 2022, I suspect).

In case others are experiencing it, here are some breadcrumbs to follow:

This page explains that you now need to use a version with a built-in browser. Since I can't start QB to install, that page directed me to this page to install from the Internet. That page had me install the QuickBooks Desktop Manager which told me to uninstall QB 2020 using Windows. Attempting to uninstall it resulted in the message, "The installation was interrupted before QuickBooks could be installed." So I renamed the folder "C:\Program Files (x86)\Intuit\QuickBooks 2020" to "QuickBooks 2020 (old)" and restarted the QuickBooks Desktop Manager. The Desktop Manager failed (at somewhere around 40%) with a, "Fatal error during installation. Error code 1603." I chatted with QB support about that error, they arranged a callback, and the callback hung up on me after saying, “Sorry we missed you. Please visit our website for support.” And it hung up on me. OMG!