No, the qubbutzim are great, I think, but are they really socialist? Do they allow some to live off the labors of their brethren? The initial version of the Plymouth Colony was also rather like the qubbutzim, but almost died from that problem, before moving to private property.
Apart from the soft socialism of W. Europe (which is failing), modern socialism always seems to be highly coercive, from the Soviets, through the Nazis, to China and Pol Pot.
Why do Jews not reject socialism, after their experiences under National Socialism?
You got me.
Why do Jews who don't believe in HaShem or Torah (and who believe that one day the entire human race will become extinct) worry themselves into a stroke over "Jewish survival" and a "Jewish mission?" It makes no sense, does it? Yet they do. They may not believe in HaShem or Torah, but they're "still Jews," which means (they seem to think) that they must survive for some reason or other and critique the host society.
As I keep saying, these tendencies are not bad in themselves. They were placed in the Jewish soul by G-d so Jews would conquer the world for HaShem. But when Jews reject Torah and HaShem the Jewish soul becomes terribly destructive.