It makes sense to use the current industry standard (React Testing Library): it’s just likely to be more time-consuming to rewrite the existing tests to it. However, FED-BOM would still prefer to use RTL, and since they’re going to do the brunt of the work across the frontend repositories, there were no objections.
Some repositories - likely the ones owned by Aurora - will use react-unit-test-utils, but that’s also ok. One of the reasons to have MFEs in the first place is to give code owners some freedom in decisions of this kind.
Unit vs Integration tests
Unit tests are a way to document what the code should do and also speed up development iteration, so they should definitely not go away
Integration tests are valuable too, but one does not exclude the other
Ideally tests are written using both techniques where they’re best applicable