SEO

Is duplicate content cannibalizing SEO traffic/ranking?
If i have content that overlaps will google downrank both pick one or rank both?

Content duplicate is in no way healthy for SEO. Infact, that one criteria you must meet to get ranked and qualified for google ads is content uniqueness..

In your case, google considers the first post it crawled and ranks it over the other

You must stay unique and relevant if you must scale up and succeed on the internet.