Nice work on the solution for modern SharePoint online sites!
I added it to one of my sites, where I have a catalog of applications. The catalog has a dropdown choice field named ApplicationDisposition. If that dropdown has a value that is not blank, “Pending” or “Deployed” I want a multiline text field named ApplicationDispositionReason to become visible; in all other cases, the multiline text field should be hidden.
I made a rule that I believe should work. It does initially hide the multiline text field because the default ApplicationDisposition is “Pending.” However, it does not show the field when I change the ApplicationDisposition to “Deployed.” I have also tried a similar rule where I had an action on the “No” side to make the multiline text field visible, and that didn’t work either.