ok then two comments:

• if nothing is strictly true, then that implies that the statement that "nothing is strictly true" is also not strictly true, i.e. there are exceptions which are strictly true ...

• jokes aside, your comment reminds me of a funny story i once read where a biologist does research on clover (you might know this one). he investigates all clover he can find and finds that they all have 3 leaves. so he calls it a law of nature that clover has three leaves.

one faithful morning, he walks out of door and finds a 4-leaved clover in the garden (which is symbol of good luck in some cultures). however, he rebukes at that and tries to sue the clover for violating the law of nature ...

kinda the same spirit as what you said above. people make observations, then make these observations into laws, and if somebody breaks them, that's their fault. instead, the model was conceived inappropriately .

It's about as artificial as the concept of 'nations' I feel

Is there such a thing as real taxonomy

in the unlikely case that this is a serious question: yes, there is, at least for eukaryotes.

for eukaryotes (things that have a cellular nucleus) there are "species" which are groups of organisms that can't produce offspring with each other. The reasons are typically (i think?) that the genetic differences between two species are too great and any offspring would therefore have such a self-incompatible set of genes that they cannot live with.

for prokaryotes (bacteria) the situation is a bit different. due to horizontal gene transfer, they can exchange genes with practically ever other strain of bacteria, as long as the environmental circumstances are right. (and the result is often viable, i.e. the resulting bacteria can live that way). as a consequence, there are not so clearly defined "species" for bacteria. however, there are still groups of bacteria that have a higher similarity to each other, so we still group them together and give them names.