Yes, the Old Testament is drastically misunderstood by those unwilling to take it seriously. I encounter these same objections so much, and they influence how people view biblical Christians. We aren't, or at least shouldn't be, selective about what parts we obey. We aren't national Israel, we are in Christ in this dispensation of grace. We aren't under that law system. It's purpose was served and it is no longer in effect.
Remember, never read a Bible verse. Anything that can, will be ripped out of context and misappropriated.