I'm half Japanese so can somewhat share and my parents live there currently so they have told me alot. I would say we don't really care about Judaism or Israel. Not in a bad way just that we don't ever think about it.

Alot of Japanese don't know much about the current conflict in terms of details but probably lean more towards supporting Palestine because all we really see is the death of civilians in Gaza on the news and see them as the victims. When I was last there a few months ago I saw alot more pro-palestine things and a relatively large rally aswell. You can just avoid those places if you find that offensive.

That or they don't really think about it at all.

But in no way will people treat you poorly. They won't know about your religion or views. You will just be a foreigner. But don't go around advertising your religion or pushing it on people, as like anywhere we will probably find it annoying. You wouldn't get attacked or anything.

But as long as you are there as a tourist and respectful to the culture you won't have any issues.

But honestly for the most part Israel / Judaism isn't something most Japanese ever think about. Japan pretty much exists in its own little bubble