I would be very surprised if the majority, or even a significant fraction, of those who are on the "Israel" side were observing Jews. Jews are probably a minority of Israel-supporting commenters, and observing Jews are, in my experience, a minority of these Jews.
"submissions on the topic have ended up flagged and we haven't turned off the flags." only because they were flagged before getting traction.
Saturdays - Observing Jewish people don't check HN on a Saturday, and they are one of the major side of the story here, unsurprisingly.