Even the digital property liberators/internet pirates don’t test their software. I feel like I’m on an island with a small population of test enthusiasts.
Ultimately, what's the point. The tool either works, or it doesn't. Then you patch what doesn't work so it does work.
Heck even the Linux kernel isn't tested.
Unit tests are so management can have a good metric to sell code quality. I don't know any time unit testing has actually benefited shipping faster (which really is the only bottom line those above you care about)
It's of huge benefits to me when I have to make a small tweak (fix a bug, or add a new specific corner case) into an existing codebase that I didn't write and don't know very well. Being able to make a small change and being confident that it will not send everything burning in hell.
I have worked on large systems devoid of tests. Not recommended. I literally witnessed multi-million dollar losses that would have been prevented by requiring tests.