The Ashkenazi uber IQ myth, which conveniently appears after Jews start really dominating finance and universities in the 60s onwards, is really just a clever smokescreen to calm people who have serious questions about why 2% of the population control every major power structure. The first major book arrives a few years after the foundation of the Federal Reserve as John Spargo's 'The Jew and American Ideals' that promotes this as a reply to Henry Ford's 'The International Jew', but it was then heavily used during the 1930s and 1940s as 'anti-Nazi propaganda' having its major work - Cecil Roth's best-selling and error-ridden 'The Jewish Contribution to Civilization' - published at this time but there are multiple other examples of it being invoked in shorter form around the same time and earlier (Arnold Zweig's 1934 'Insulted and Exiled' and Sidney Osbourne's 1939 'Germany and Her Jews' etc).
It then got heavily propagated after the war into religious circles by the jew Max Isaac Dimont, who wrote his best-selling 'Jews, God and History' as a long claim of jewish superiority over non-jews with a religious patina as to appeal to 'Christians as being converts to a form of Judaism'.
Most of the evidence for Jewish IQ relies on shaky tests of poor sample sizes from the 1960s and 1970s, and many of these tests are used - by people like Steven Pinker (a Jewish supremacist evolutionary psychologist who is in the Epstein Files) - to demonstrate the likelihood of high IQ, but are not actual IQ tests in and of themselves. Number crunching data from Israeli student academic performance averages (below every single European country) and IQ tests of IDF soldiers gives a pretty banal number for Jewish IQ level, 98-101, which would be higher than East Mediterraneans but identical to most of Europe.
We have autosomal genetic data for modern human ethnic groups, and Jews are not unique. They sit on the East Mediterranean genetic cline, alongside South Italians, Maltesers, Island Greeks and Cypriots, and are extremely close genetically to these groups despite isolation and inbreeding, which has inflated their FST distance. East Mediterraneans (sorry Sicilians) have the lowest average IQ levels in Europe, and frequency of their male haplogroups in a population correlate with lower IQ levels also. This doesn't mean they don't produce scientists, geniuses and clever people, it doesn't mean they are on the level of an African, but it does mean their baseline IQ is actually slightly lower than other White Europeans. If the Jewish average IQ of 107-115 is true, it means they have a mindboggling IQ advantage over people genetically almost identical to them greater than people who have been evolutionarily separated for 50000 years. For reference, Koreans and Japanese people have the same genetic distances Ashkenazi Jews have to Cretan Greeks, and their IQ averages are identical. Also, even though it's connection to intelligence mostly considered a pseudoscience today, it should be pointed out that in the craniometry surveys of physical anthropologists like Carleton Coon and Bertil Lundman, Jews tended to have slightly smaller skull and brain sizes on average than White Europeans (and White Europeans had slightly smaller skull and brain sizes on average than Scandinavians).
Another common argument is that Jews practiced eugenic marriage of scholars and the wealthy, and constant repression make the Ashkenazim develop unique mental faculties. But most of the Jewish population was rote learning scripture just like most of the Muslim population, and most Jewish wealth historically comes through moneylending, which isn't particularly mentally taxing. You might ask yourself, why have no other religious minorities undergone this rapid selection for intelligence due "suppression" and "scholar marrying" like the Ashkenazim purportedly have? Where are the uber IQ Druze, Ishmaelites and Alevites? They encourage their scholars to reproduce and they underwent repression for 100s of years, but they don't control the fed and every newspaper.
"But the Jews are overrepresented in Nobel Prizes! Surely this is a sign of uber IQ!" Firstly, A lot of 'jewish Nobel winners' - especially the earlier ones - are part-jews (usually 1/2 to 1/4) who didn't identify as jewish in their lifetime (e..g., Adolf von Baeyer) plus one gentile convert to Judaism who is usually falsely lumped in as jewish (which is a contradiction in terms). There are several 'jewish winners' whose priority for the research that got them their award is subject to strong doubt (for example Gertrude Elion for 6-Mercaptopurine for when she was just a glorified lab assistant to George Hitchings and Hitchings all but later stated that Elion had filched his research; another is Baruch Blumberg who basically stole Alfred Prince's research on Hepatitis B and was awarded a Nobel Prize for it in 1976; another is Selman Waksman who stole Elizabeth Bugie's research on Streptomycin and presented it as his own to get the 1952 Nobel Prize for Medicine etc). Jews actively prevented other non-jews whose work they stole from getting Nobel Prizes for example Paul Ehrlich basically stole the work of Sahachiro Hata on Arsphenamin then deliberately hobbled three attempts to get Hata a Nobel for its discovery (in 1911 for Chemistry as well as 1912 and 1913 for Medicine) because Ehrlich had publicly stolen the credit for the discovery with the assistance of jews in Hollywood (specifically the Warner Brothers). The closed process of prize winner selection has a bias towards Jews, as there have been instances where scientists as influential as the man behind the 1000 Genomes Project was skipped over for a Jew who did research on Annelids. As Swedish academic Jan Biro has pointed out the 'jews have won so many Nobel Prizes' argument actually shows the opposite of jewish achievement when contextualised with patent filings and percentage of jewish population. In reality, data demonstrates Jewish presence/percentage doesn't correlate to invention/innovation at all, while the Northern European presence/percentage within a population does. Scandinavians have the highest rate of innovation per capita of any race on planet Earth.
Yet another problem is the lie that the arrival of Ashkenazi Jews in Western Europe are when Jewish takeovers of the institutions begin (because their uber IQ made them simply outcompete all the White people fair and square, duh!). This is untrue, Sephardic Jews have a long history of the exact same phenomenon. Sephardim were infamous for their overrepresentation in both Visigoth Spain, the government of Al Andalus and early Castille prior to their expulsion, as in the case of the converso over-representation in Juan Alfonso's court, which lead to riots. They were also hugely overrepresented in shareholders of the incorporated Bank of England central bank, as well as on the Dutch Stock exchange (as Sephardic crypto Jews from Spain and elsewhere flooded the Netherlands), so this over-representation is not an Ashkenazi phenomenon. Ashkenazis do appear different to Sephardis, but only in the sense they're more schizophrenic and insane, whilst Sephardim prefer to stay totally out of the limelight