I find the common definition misleading, because it implies that humanity is not part of nature. It is technically false, and causes confusion in the mind of most people.
The "natural good, artificial bad" meme needs to die.
We're currently facing ecological problems of immense scale, and not having a proper basic mental model of the situation is detrimental.
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.
> ... the generally positive connotation of “nature”.
"Nature" is inherently hostile (see Thermodynamics, 2nd law). What's currently marketed as "natural" is a carefully vetted subset, the result of thousands of years of humanity influence on its environment.
As you mention, the definition of the word has been evolving. I think the current meaning is misleading. It causes people to reject man-made things arbitrarily, and, more generally, it perpetuates an anthropocentric view of the world.
Wishing it had (and advocating for) a saner definition is not silly.
Why do you think it is "tilting at windmills" for me to want the definition to change to something that pleases me?