I can't help but suspect that many people hear the word "aliens" and immediately tune out and just hear new age woo becoming insensitive to evidence that doesn't match their expectations. This makes some people couch their words in terms that aren't offensive to those who already "know everything".
I don't think we'llever know anything at all about far ancient times unlress we put everything back on the table and go back to the drawing board. What we're doing isn't working and except for genome studies we know little more today than we did a century ago. But DNA mere tells us WHO the various ancient peoples were. It doesn't tell us how they lived and what they believed. It doesn't tell us why they did what they did or how.
We are as much a species with amesia as we were 500 years ago. We didn't know our past then and we don't know our past now. We are painting a picture that looks just like us instead of assembling the jig saw puzzle that was left by ancient civilizations.