I deeply know IE 🤣 I am grateful that I almost do not need to give support to it.

One thing that it is useful about TDD when you have practice, that you may like, is that it allows boldly to change the code. You really do not need to think that much, you just make the change, run the tests, and if it does not work, undo and try a different approach. And of course, you do not need to nail everything in the beginning, with TDD you can evolve the architecture during the development and avoid having unnecessary extra complexity.