Have you actually looked at his project ? It's a library that helps you write tests by generating dummy data - even if this was GPL it would have no impact (except maybe scaring some people from using it or making it a non starter in companies with policies banning GPL). You will never distribute your tests to the client and if you're running test you already have access to the code.

And this is trivial but tedious code that you could replace on the spot.

I'm not dissing the author but these rants about opensource licensing and whatnot are completely out of touch.

Most (but importantly not all) of serious non-trivial open-source is sponsored by big corporations or academia so this stealing narrative is ridiculous, and MIT/ Apache is an excellent licence that successfully facilitates collaboration on some of the largest OSS projects out there so there's nothing wrong with using them.