titanmelon said:
The definition of 'anthro', compared to 'anthropomorphic'

It's a short for an 'anthropormophic animal'. Which is quite a mouthful, so it's no wonder that the fandom shortened it.

The anthro wiki entry might need some work. It seems a bit too wordy at the moment: it only gets to the actual usage of the tag in the last sentence of the first paragraph. If I have time, I'll see if I can re-order it a bit.

If someone's primary familiarity with animal physiology comes from talking animal animated family films- whose characters need to be given 'human' expressions and reactions for film-reasons- then I'm not too surprised if the difference seems inconsequential to non-existent

I suppose we could consider adding a feral subtag for 'realistic ferals' (100% anatomically correct, no hints of anthropomorphism at all). But while it would be easy to tag for real-life animals, I can see several problems with tagging fictional and mythological ferals, such as dragons...