The first claim is both true and not true.

The complicating factor is that cultures and ethics and tendencies are handed down from generation to generation, and tend to remain connective threads within families, and thus ethnicities, as such. Feel free to think smaller if desired - the branches of my family are very different from one another, and all have different behavioral traits dependent on the patriarchs, but also all have common traits that make us clearly different from other family trees. Just write that larger for ethnicity - the main difference is scale.

There are also generational blessings and curses in play.

Both these things can be broken. Being a tendency or proclivity does not dictate that a thing will or must continue to be. We can and should show love to anyone at individual levels in order to bring them into the fold. To your second note, that is why it can be made to not matter and not make or break a society, but the integration must be much slower than it’s been done - not just for the last 10 years but the last 150 or more.

This is not the first time the cabal has attacked nations with immigration, just the most obvious one.