Well, I really think that the reasons are different.
First it is overhyped, and at the same time, undervalued. It is overhyped by those who claim to know TDD but do not know how to apply it correctly. For example, I have seen countless people following blindly TDD but in a wrong way, so they lose almost every benefit from it. But I do not why, those people love TDD, and I do not know why because what they do is almost pointless, but at the same time, they talk about TDD as it is the cure for the cold. That is insane, and that is why it is overhyped. But in the side, TDD really comes with plenty of benefits, and because most courses and resources only focus on the QA part (and that is why most of the people do it wrong, TDD is nothing about QA). And that is why I wrote the Why to test pyramid because, that, and many of other concepts, are undervalued.
Second, agree. But it is also because there is a big deal of pushback, and also because people stop, and not even do, the easy examples. For example, Robert C. Martin has a video of almost 4 hours explaining how to face a project from start to end using these methodologies, but not everyone looks for it. There are plenty of good example, unfortunately, among even more bad examples. But what happens with the good examples is what happens with the Robert C. Martin's Bowling Kata. It integrates countless valuable TDD concepts, and can be completed in 20 minutes or so. Yet, when presented to other people, so they can learn from good examples, they dismiss it, and they assume that with a small read of the three rules there is enough. So, it is not strange that you cannot find good examples, the search algorithm do not favor them.
And some of the concepts that you talk, about "uglify" the code, etc. are the ones that David Heinemeier Hansson published in "TDD is dead. Long live testing". They came because he focused the testing wrongly. But fortunately, unlike many other people, instead of claiming that TDD is great, he saw that it did not work, and not added hype on top of bad practices.
