No, high Jewish IQ scores are mainly due to Ashkenazi Jews' higher IQ, so the Israeli average IQ score could be lower because of a lower percentage of them living in Israel than in the rest of the world.
And in fact that is exactly the case,
'Many studies show Ashkenazi Jews as having the highest average IQ of any ethnic group, eight to fifteen points higher than Europeans and leading East Asians, who also score highly. These studies also indicate that this advantage is primarily in verbal and mathematical, but not spatial, areas.
Today, Ashkenazi Jews constitute approximately 80 percent of world Jewry, but probably less than half of Israeli Jews.'
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