This is a really silly argument. There is a wide variety of definitions of “nature”, which has gone through dramatic changes in its meaning though the centuries. Criticizing definitions you don’t like because the generally positive connotation of “nature” lets those definitions serve a rhetorical position that you disagree with is tilting at windmills.

In particular, the sense of “natural” having to do with something’s unaltered/innate condition – as compared to some result of human interference – dates back at least to Plato [well, there the word was the Greek phusis, whereas natura is the Latin word used to translate it, but you get the idea]. Or if you want examples in English, at least to Chaucer.

Note, if you want a much fuller idea of what “nature”/“natural” means and meant in the past, I highly recommend the CS Lewis book Studies in Words which devotes a 50 page chapter to comprehensively exploring the subject.