“Ironically enough, Ashkenazim began eating turkey when they saw Sephardim eating them. They (erroneously) assumed that their Sephardi brothers must have had a Mesorah that a turkey was a Kosher bird and therefore they could rely on the Sephardi Mesorah. “
Interesting. but not necessarily so.
when turkeys were introduced there was a lot of halachik discussion as the its kashrus and some tshuvos exist.
but somehow the turkey became accepted.
What I have read that exactly how turkey became widely accepted is lost to history.
The idea that it was accepted because it is like chicken, I find that very implausible.