One of the sore points in Jewish evangelism is the position that Jews are damned unless they believe in Jesus (i.e. the messianship, deity, and Incarnation of Jesus). Of course, that’s not unique to Judaism. That’s standard exclusivism, which applies to non-Christians generally. And there wouldn’t be much point evangelizing Jews if it didn’t matter what you believe about Jesus.
Many people naturally resent being told they’re hellbound unless they become Christian. Suppose, though, we turn this around. Imagine if Christianity said all Jews are going to heaven. Would Jews be impressed?
Religiously conservative Jews think Christianity is an idolatrous, polytheistic heresy. So why would they care if a false religion gives their own religion the thumbs up? Isn’t a Christian endorsement of rabbinic Judaism worthless from their standpoint?