The author made one slight mistake: he wrote "there is a tendency to mindlessly modify code" instead of "I have a tendency to mindlessly modify code".
Also, it's not like this we haven't seen this kind of behavior decades before the invention of TDD.
This is just another example of a craftsman blaming his tools. TDD is not a silver bullet, but no method or tool can serve as an excuse for mindlessly poking around until it works. This isn't limited to programming either.
If I only were in the past. I've seen this behavior with coworkers, changing random bits of the code, without any coherent system to speak, rerunning the application from scratch and manually testing if it works now.
He also completely overlooked the refactoring part of the equation, too: write test(s), write code that passes all the tests, then refactor the code until it's shiny enough and still passes the tests.
I also have the same problem the author has sometimes: If I know that there are a lot of tests covering a particular piece of code, I tend to be less diligent making modifications
Also, it's not like this we haven't seen this kind of behavior decades before the invention of TDD.
This is just another example of a craftsman blaming his tools. TDD is not a silver bullet, but no method or tool can serve as an excuse for mindlessly poking around until it works. This isn't limited to programming either.