The things above water are the things that can "change" with immigrants, leading to the illusion of assimilation pic.twitter.com/j0YWJWneOd
— JayMan (@JayMan471) May 9, 2016
It's been around for a while as the Cultural Iceberg; but as JayMan says, the easy-to-see features above the waterline are just those likely to give the illusion of assimilation.