The modern (creepypasta) incarnation of the wendigo has grown antlers – a feature not present in the folklore as far as I'm aware. ...
This dis- or mis-association of antlers and / or other animal features to the wendigo runs deeper than Euro-derived New World folklore.
The Native American (primarily Algonquin-related) groups from which the wendigo stories came didn't characterize the wendigo as a material monster or cryptid at all.
Instead, the wendigo was consistently described in terms of a human possessed to eat human flesh - almost always explained as emerging during famine conditions but sometimes additionally glossed as resulting from influence (e.g. manipulation; curse) from an ephemeral spirit entity encountered in dreams or visions.
In the cases where such a spirit entity was allegedly involved this entity was sometimes characterized as being a, or a variant of a, particular animal's guardian or representative spirit.
The mutation of the wendigo spirit into a generalized Evil One motif, and further into an allegedly material monster / cryptid, occurred among the Euro-colonists and their descendants.
For the Native Americans the wendigo represented a form of human possession or psychosis. There were isolated cases or folkloric lineages in which Native American stories alluded to giants who killed and ate humans, but these were described as mythic / spirit entities (rather than material monsters or cryptids) who inspired or instilled the wendigo mania in ordinary humans.