While saying "it's an herbicide, not a pesticide" is categorically incorrect, I still think it would be better if the journalist used the more specific and less confusing term here.
I'm not trying to be pedantic, I've literally never heard of pesticide used to mean anything but bug killer. I guess you are technically correct?
> Pesticides are substances that are used to control pests. They include herbicides, insecticides, nematicides, fungicides, and many others (see table). The most common of these are herbicides, which account for approximately 50% of all pesticide use globally.[0]
[0] https://en.wikipedia.org/wiki/Pesticide
You're trying to be pedantic, but you're actually wrong. If you think about it, from the perspective of anyone trying to raise crops, weeds are pests. (They are pests to lots of non-farmers, too.)
Similarly...
> A pest is any organism harmful to humans or human concerns. The term is particularly used for creatures that damage crops, livestock, and forestry or cause a nuisance to people, especially in their homes.
> Plants may be considered pests, for example, if they are invasive species or weeds.