I dug a bit further into the matter.

The one changing the surname wasn’t this guy Benjamin, but his father Benzion Mileikowsky → Benzion Netanyahu. He did it as settling in Israel, as it was customary for Zionists.

Relevant quote from Benzion:

“The tendency to conflict is in the essence of the Arab. He is an enemy by essence. His personality won’t allow him any compromise. It doesn’t matter what kind of resistance he will meet, what price he will pay. His existence is one of perpetual war,” he told the Maariv daily in 2009.

I don’t usually talk politics through this account but what a sorry excuse of a human being.

(My own city Curitiba is a counterpoint to that. As much shit that might happen here, even with somewhat expressive Arabic and Jewish immigration, we never had any serious issue with them. So “perhaps”, just “perhaps”, the Arab-Jewish conflict is not caused by the nature of either, but by the State of Israel’s Lebensraum policies???)

He tried to change his name to “Ben Nitay” while living in the US.

Maybe their family members committed acts they didn’t want to be associated with.

Is it possible that the current argetinian president, Javier Milei, was ancestrally named Mileikowsky also?