I worked through troubleshooting with a phone support agent. They were not able to solve the problem on my computer. The installer issued an Unexpected Windows Error 65535 every single time and uninstalled the software itself. They suggested I use the online version of TurboTax instead. Seriously. Eventually I gave up and I was actually able to install it on a different Windows 10 computer with no special effort. But this is terribly unacceptable. It should install cleanly on any modern Windows 10 computer.
Anyway. My solution to get it working on the first computer was to perform the install on the first computer where I was having problems and then to kill the installer in the task manager when it reached 100%. Then I installed it on the second computer with no problems. Then I transferred the C:\Program Files (x86)\TurboTax\Deluxe 2019 folder from the working computer to the non working computer. Then it ran fine on the first computer.
This solution is completely unacceptable for the normal user.
