My view, and I think this is similar to
@Doug McCrae's view, is that what is at issue is
tropes and related ideas.
Consider Lizardmen/Lizardfolk: they are (literally) presented as resembling certain animals; they are also presented as culturally closely resembling a stereotyped conception of "native" peoples: they live in "huts", they use "primitive" tools and weapons, they practice exo-cannibalism, etc.
One school of thought has it: we use Lizardfolk so we can enjoy those pulp tropes but not associate them with any actual human peoples.
Another school of thought, which I personally am closer to, has it: using Lizardfolk keeps alive these tropes which have no cogency or currency except as byproducts of the racist ideologies connected to European colonialism particularly in Africa and Asia. It's the tropes themselves that carry this baggage and hence keep the racist ideas alive.
When is something tripe and when is it a natural feeling story element?
It feels like human shaped animal monsters have a long history in film and pop culture and myth - creature from the black lagoon, yeti, hundreds of things from folklore collected in the PF bestiaries.
Do Tanuki and Vanara and Kappa and Minotaurs and Satyr, etc... need to be people in masks with no innate personality traits or differences in mental processing than real people?
Would a humanoid bower bird build a really really fancy hut? Would a humanoid beaver? If we have a lizard brained lizadish humanoid or would it live in a burrow or would some lizards build artificial structures if they had opposable thumbs? Would a humanoid coyote or wolf do things that looked like worshipping the moon? Would a humanoid elephant venerate the dead?
Would a humanoid version of a territorial apex predator reasonably still want to be a territorial apex predator in competition with people? If it was, would people not compete with them? Could a slightly smarter gorilla species possibly be made more erudite than humans , and another play up the bestiality? If the later, do we have to avoid competition between them and humans to avoid any awful tropes (I'm sure I can find some horrible racist pictures from not long ago to show they're still in use). Should we just entirely avoid some species to humanoidize?
If we want to have some more advanced than humans in terms of technology or magic is that problematic? Can we have some be less? Would more intelligent than dogs but less than human dog men not build artificial shelter when a cave wasn't around? If it happens that some designs are the ones that are obviously more effective, would we need to avoid those just because some real groups of humans did/do use those? If the base species is cannibalistic, does that need to be avoided in the more humanoid one to avoid problems? Real otters use tools, would humanoid ones either need to use the full suite of human tools or none of them to avoid using only "primitive" ones?
Does the creature from the black lagoon need to have language and literature and science and live in a house to avoid tropes?
Is it ok to just have the things the races do semi-logically follow from what the base species does? Is it ok to have a species that uses all body tattoos or feathered head garments or... as long as the patterns don't look Maori and they aren't used for an island dwelling sea exploring race obviously met as a stand in? Are feathered head coverings ok as long as it doesn't look like something used by a real tribe in the US for a fake species that lives in that ecosystem and doesn't use stereotypical things like totem poles or teepees?
If there is a wizard-made rat people, is living in the sewers, being generally looked down on by people, and not being afforded the same opportunities as those on the surface an ok space to play in? Or can I not explore some of the things Glen Cook did with that in his Garrett series?
It feels like there's a big place out there that allows for humanoids that aren't just people in masks and that aren't just lazy tropes. Is it just that doing so takes work and we'd have to recognize it will probably still inadvertantly hit something even if being careful? (And recognizing that many things from the past didn't care at all about trying or being careful).