After upgrading to InDesign CC2019 to 2020 and resetting my preferences, I've been having problems with the text tool and selecting objects in some of my .indd files.
One problem is that I am not able to select the text tool with a keyboard shortcut. Here is a gif of me simply pressing "T" a few times. The cursor changes for about one second, then changes back. The tool bar shows that nothing actually changes. Clicking the text tool on the tool bar will to change it, but only after InDesign freezes for a couple seconds.