Early in the 1900s for a very brief period eugenics was thought to be a way to rid the world of disease, before it became clear what it would entail. The amendment to ban alcohol and the amendment to unban alcohol were both part of the progressive movement as well. So nailing down what is centrist, progressive, right wing is very much time dependent.
Abortion was very much popular in non catholic churches until the 1980s when republicans roped it into the culture war.
Idk if "descendants of omnivores" counts because then you could exclude a number of critters like pigs for being "descendants of herbivores" and then 'why do pigs have forward facing eyes?'
The obvious caveat is that pandas at the minimum don't have selective pressure for side eyes or they have something pressuring stereoscopic vision even more similar to how aquatic animals have less selective pressure for forward facing eyes.
I would imagine the way pandas eat bamboo stalks is more visual than most herbivores and that alone could help them retain steroscopic vision.