I did not read the article. I did read all comments
Unit tests for the most part aren't about "testing". They are developer tool. To verify rthat modifications (refactoring, additions, bug fixes, etc) doesn't break contracts etc. Oh and showing that your code is a codependent mess of poorly isolated spagehtti, if your unit tests are hard to write, the code under test is a mess. Inittests are more useful in languages with loose or poor type systems.
Many unit tests are not written well. testing more than the interface/contract. Or full of complexity boilerplate and mock. Which means code needs fixing.
Unit tests for the most part aren't about "testing". They are developer tool. To verify rthat modifications (refactoring, additions, bug fixes, etc) doesn't break contracts etc. Oh and showing that your code is a codependent mess of poorly isolated spagehtti, if your unit tests are hard to write, the code under test is a mess. Inittests are more useful in languages with loose or poor type systems.
Many unit tests are not written well. testing more than the interface/contract. Or full of complexity boilerplate and mock. Which means code needs fixing.