Actually, quite a few Christians have read it. Many of them find it a feature, not a bug, that Jesus teaches from the Hebrew Bible. It is difficult to imagine how any book could be read by one or two billion people, without some people misreading it. If such people are typical in your experience, then maybe that says something about your sampling method, and not so much about the population you're sampling from.
You might also recall that even in the New Testament, Jesus doesn't always "come up with" the formula. Luke 10: 25-28 has a "scholar of the Law" (that is, somebody who knows the Hebrew Bible) give it as his answer to Jesus' question, and Jesus approves of this answer.
As we know, that these verses could be taken as summations of Torah was a view with adherents at the time, quite apart from any Jesus movement. Jesus is depicted as aligning himself with them on this point, just as he is aligned with the pre-exisitng John the Baptist movement. The New Testament view is that Jesus is consistent with the best traditions that preceded him, not that everybody got it wrong until he showed up (perhaps you are confusing Christianity with Islam, I notice that many atheists do.)
Speaking of Jewish precedents for Jesus' teaching, the Matthew 10: 35-37, which you find so revealing of Jesus, is a paraphrase of Micah 7: 6. That chapter as a whole is an invictus poem. Jesus seemed to like those, and might sometimes quote part to convey the whole, although his doing that carries the danger that those who don't catch the reference will misunderstand. Compare Jesus' very abbreviated recital of Psalm 22 on the cross, often mistaken for a moment of doubt.
So, yes, all this is revealing. Turns out that Jesus was a well-read Jew. No doubt you can find, have found, Christians who are surprised by that, but it is a little odd to judge the cogency of a position held by billions by its least well-informed adherents. That policy does economize on the amount of effort required to engage them, however, so it's not completely unfathomable.