If people could travel east and land on Easter Island, why couldn’t they travel east from EI and land in South America? Also has the genetics of Easter Islanders been compared with these South Americans?
It’s a good speculation but they can only really go on what the evidence says. The genetics of Easter Islanders has been studied. They are/were Polynesians not Australasians so this particular study doesn’t involve them.
There was an interesting discovery of contact estimated to have occurred 800 years ago between Polynesians and the New World. Some modern Polynesians carry Native American DNA from that contact.
https://www.livescience.com/polynesians-native-americans-dna.html