EDIT: After deleting all of my angular modules' .iml files and recreating the modules from existing sources, everything works again.
Angular syntax highlighting was working fine in IntelliJ 2019.1.3 (build 191.6183.87). After upgrading to version 2019.2.3 (build 192.6817.14), none of the angular bindings and directives are highlighted in templates, and ctrl+click does not take me into the code. When I upgraded I simply allowed IntelliJ to pull my IDE settings from the previous version.
I tried disabling and re-enabling the AngularJS plugin to no avail, and I do wait for indexing to complete.
If I open back up 2019.1.3, it loads my same project that I'm using in 2019.2.3 just fine with the Angular syntax highlighting and code completion working just fine. When I switch back to 2019.2.3, it is still broken.