Yes, you're correct but that's why I said it was a "working" definition. When you're a botanist (like many of my former professors) you still use the word vegetable in discussion. They would often teach us about local plants with indigenous uses using plain language like "the Chumash used the leaves of this plant as an important part of their vegetable intake", rather than using some clinical term like "edible plant matter" or whatever.

I was only saying in these contexts, they definitely wouldn't describe fruits as vegetables because fruit are a specific thing to a botanist. They definitely wouldn't describe fungi as vegetables because they are also a specific thing to a botanist (not relevant 😂)

So in a scientific setting the word vegetable is still used, but it is mostly defined by what it's not!