Let’s get real.
You may be suffering from the false consensus effect: where you tend to overestimate how many people agree with your views.
“TDD is a cult, hardly anyone does TDD”
The popularity of TDD is easily tested, and quantitative statements about it are easily verified or, as in this case, decisively debunked.
- ~143k StackOverflow questions mention unit tests.
- ~47k mention functional tests
- ~22k mention TDD
- ~10k mention BDD
By way of comparison:
- ~37k mention functional programming.
- ~42k mention OOP.
From this we can probably surmise that unit testing compares favorably to both functional programming and OOP in popular use.
Almost 100% of programmers do one or the other, or both of those. I’m not prepared to say that close to 100% of programmers write unit tests or use TDD, but I am prepared to say that the majority of software developers are at least curious enough about it to try to learn more.
Unit testing is by far the most common type of automated software testing.
See Google Trends:
Most posts omit any mention of automated testing, possibly because they take it for granted. Absence of evidence is not evidence of absence.