I think the greatest godol who supported Zionism and the medina was the Shu”t Mishnas Sochir, author of Eim Habonim Semaycha. About him was said that he was clear in kol hatorah kulah, niglah and nistar, on the level of the GRA. His Shu’t are amazing in bekiyus and charifus in all areas of torah!
The descendants of the Erev Rav were against hakomas hamedina because they had no chelek b’aretz. To them, shivas Tzion, the return of yidden to Eretz Yisroel is WORSE than Uganda, where they WOULD get a chelek in.
Some of the descendants went to Yeshiva and became lamdonim. Being a lamdon or a “godol” does not mean he cannot be from the Erev Rav! Nor is it derogatory to assert that a lamdon/godol can be from the Erev Rav. Acher was a lamdon and a godol, so were others who were off the derech! These lamdonim had talmidim and followers, some were swayed by the false shitos of their teachers.
In turn, they also became communal leaders, rabbonim and gedolim, but they were spreading the learnings they were mekabel fromm the Erev R