I see a good case for my company to use Lit for creating complex components such as highly interactive panels/widgets to be shared between React/Angular apps in our large ecosystem. However the decision was: 1. Prefer sharing plain JS/TS over framework code so try that first and 2. if the component is so complex and tricky to get right, it probably needs to be re-implemented in each framework anyways (or some sort of wrapper)

My secondary concern with Lit is the additional complexity of using shadow and light DOM together in long lived React/Angular apps. Adding a new paradigm for 75+ contributors to consider has a high bar for acceptance.