I like TDD when I’m mostly dealing with functional/library like code where I have a solid understanding of the interface/api.

Just put all the expected input/outputs in a big table test and iterate.

TDD is awful when you don’t have a clear idea about the interface and need to mock a whole bunch of internals that are likely to change.

Count yourself lucky then. I've tried to work with TDD cult members and it was one of the worst experiences of my professional life. A good sign that people have moved into the cult is when they start saying that people who are not using TDD are "unprofessional" or produce "shit" code.