I don't see it, personally. To me, the Sephardim and the Ashkenazim just look like northern Near East people with additional "European" specific ancestry, and maybe a dash of Khazar for the Ashkenazim. In every PCA plot I've ever seen, even those by the amateur bloggers, they land north of Cyprus, overlapping with some southern Italians and Greeks if the resolution is not very fine grained, and then with some of the Ashkenazim drifting a little northward toward the Tuscans and Balkan people, and with some drifting even more toward the north east, which makes total sense if they picked up some eastern European and East Asian. They don't plot anywhere near Iranians.
If I had to guess what the original Israelites of the Bronze Age were like, I'd say that something between the Samaritans and the Druze would probably be in the ball park...not the Palestinians...or, in other words, more like the current people of the more northern Near East, which would include the Iranians, just not as South Asian or East Asian shifted.
This is an example of what I mean:
I find the placement of the Belmonte Jews (SbJ) particularly fascinating. They're an isolated, very inbred group of Converso Jews who remained in "hiding" ever since the days of the Inquisition. Notice how the absorption of more Iberian input has drifted them more toward Spain.
Anyway, that's my tu cents...:)