Modern taxonomy is based on ancestory. Similarity of form and behavior are ways of assessing ancestory, but they are no longer the basis of the taxonomy itself.
You act as though there is only one correct taxonomy. Scientific taxonomy is determined that way - not cultural taxonomy. Different cultures and language groups taxonomize things in their own way. Like if you are speaking a native Botswanan language things are not divided by plant or animal it is sorted into
- Things you can eat
- Things that can harm you
- “Useless” things
Algonquin language distinguishes animate and inanimate but while plants are generally inanimate somethings like feathers are considered animate.
No one is suggesting these taxonomies should be how we categorize things scientifically but at the same time they are not “wrong”. Being able to accept multiple taxonomy systems as functionally correct is nessisary for being able to make useful judgements. In English a blackberry is culturally a berry. We harvest and use it as a berry and have named it thusly while botanically it is an aggregate drupe. Something that helps us interpret it as something closer to a stone fruit. Hence calling it a berry is not wrong. Just not fulfilling the requirements of every available taxonomy. People who are obsessed with being “correct” often latch onto scientific taxonomy but there are risks to creating hierarchy where there is only one right answer that flattens nuanced issues.
Is a fish meat? The level of adhereance to a single answer reveals the individual cultural bias of the individual. Respecting more than one answer means you can better empathize and understand where that person comes from.
You said “science tends to taxonomize by similarity, form and behaviour in isolation”. I am saying that modern science does not form taxonomies on those bases.
If you are talking about the branch of scientific taxonomy that deals with biology only then yes.
But biology is not the only branch of science that sorts things into categories. Chemistry, Psychology, Geology etc. all have different taxonomic principles based in similarity, behaviour and formation. It is fair I probably should have mentioned ancestry in the case of biology as it’s usually the first (and often only) thing people think of when they hear the word “taxonomy” but I admit glossed it over.
Probably since the taxonomy originally being referred to was botony, specifically what counts as a fruit…which is based out of formation and structure of a plant’s ovary. Not ancestry.