Because Zionists supported the Armenian genocide and The Young Turk rebels who did it.

https://www.timesofisrael.com/...

The historian recalls how many Jews loyal to the Ottomans largely looked the other way where the suffering of Armenians was concerned. This included figures such as Alfred Nossig, who helped found both the General Jewish Colonization Organization (AJK) and the Zionist Organization (ZO).

Both were set up for the purpose of Jewish lobbying across the Middle East and elsewhere, and subsequently encouraged intimate relations between Jews and Ottomans.

However, Kieser is keen to emphasize that some historical context is needed. This was a crucial turning point in Jewish history — before the Balfour Declaration was announced in 1917. Jews were looking for diplomatic favors — from a myriad of countries — wherever they could find them, in the hopes of securing Zionism’s ultimate end goal: a Jewish state in Palestine.