Finding fossils isn't a given. The record is incomplete. Most species that exist today and die off will never even leave a trace of themselves.
Also, if Gigantopithecus is the ancenstor of Sasquatch, as some postulate it as being, than it likely migrated to NA - making finding a fossil of it on this continent much less likely than finding one in Asia (where only a few mandibles and around a thousand teeth have been recovered overall).
Sasquatch tracks have been found and studied in the thousands. From the information drawn from credible tracks, a foot morphology for the creature has been somewhat established. This involves features like a mid-tarsal break (typical of primates), flat feet, and a higher degree of flexibility than the human foot. They also exhibit a longer stride, which would be harder to hoax while also generating all the other distinct features of a credible track.
There are no confirmed samples of hair by which to compare anything coming in. Here's a biologist talking briefly about having found hair suspected to be of Sasquatch origin.
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