You are quite right. The Jews are the obvious exception. But I know of no other ethnic group, at least not one that is widely distributed, that is identifiable from 3000 years ago.
There is obviously more than one possible evolutionary strategy. The Jews have for the last 2000 years followed a different one.
It should be noted that if a certain war 70 years ago had gone the other way, the Jews’ evolutionary strategy would have probably utterly failed by now.
The higher IQ of Ashkenazi Jews is widely attributed to evolutionary pressure selecting for intelligence of the bookish type, which didn’t operate very strongly in other societies.
It might be noted that in modern western societies, evolutionary pressures are apparently operating to select for lower IQ, lesser socio-economic success, etc. For the very first time in history, there is an inverse relationship between reproductive success and general success in life.
My wife is Chinese. She has told me that she can read and understand written words found in ancient Chinese records 5000 years old.
Widely distributed ethnic groups are rather rare - people have a tendency to stay put (with some spectacular exceptions during some periods, obviously)...
Jews are a distinct group who are not (and I doubt they really see themselves as) White.
The Jews survive because they always as “is it good for the Jews?” unlike Whites who always ask “is it good for everyone else?”
Jews will viciously attack anyone who threatens (or even questions) their interests; Whites will invite hostile aliens into to their countries and hand over control.
Their high intelligence and intellectual aggressiveness allow them make best use of that ethnocentric outlook. That is why we have the American Israel Public Affairs Committee but not the American British Public Affairs Committee which would make much more sense given our historical, cultural, linguistic, and racial connections to Britain.
If Whites Westerners were to adopt the same attitudes we would not have many of the problems we do. It is interesting that Jews like Chuck Schumer for the Democrats and Sheldon Adelson for the Republicans push strongly for open borders for us but want to preserve the particular ethnic makeup of Israel.
These attitudes are why Jews survive and White nations are dying. We would do well to adopt these attitudes for ourselves.