There was no specific Jewish or Israeli aspect to the In/Out vote of the UK in regard to membership in the EU. There was maybe a tendency for Jews to vote to stay in Europe, but the Jewish community was as split as most other Brits. However, now that the vote has gone the way of Brexit, we can analyze it in terms of Jewish/Israeli interests. First, let it be said that the EU is in general more anti-Semitic and more anti-Israel than Britain has been. Although there has been an increase in anti-Semitism in British universities, what with the growing BDS campaign, nevertheless the UK Government under PM Cameron has been very friendly to the Jews and to Israel. His resignation is a definite loss to Jewish/ Israeli interests. It might be that loss of British influence may result in an even more anti-Semitic/anti-Israel EU. The EU should now be too busy with its own problems to bother with trying to bully Israel.
The leave vote was dominated by negative images of immigration to Britain, both of EU members and foreign Muslims, and this could be regarded as also anti-Jewish in principle. The Leave campaign could be interpreted as a more nationalistic view of British interests and as such might be regarded as less pro-Jewish. But, Boris Johnson, the leading Conservative advocate, was at pains to emphasize that he doesn’t see this as an anti-immigration policy, and that he is a descendant of Turkish immigrants. The main emphasis of the Leave campaign against immigration, although quite nationalist, might be regarded as more anti-Muslim than anything else, and did not seem to have any anti-Semitic undertones to it.
How will Boris Johnson be if he is elected, as expected, as the new Conservative leader and new PM? It is very likely that he will be friendly towards the Jewish community and towards Israel. Britain will now need all the friends it can get, since leaving the EU has connotations of losing friends. Trade between Britain and Israel has been increasing and is increasingly technological in content. Israel has a lot to offer the UK, and so in this time of uncertainty, trade between the two countries may continue to increase. Overall,the impact of the negative vote should have no specific direct implications for the Jewish community of the UK or for Israel.