Should I respond to editors about unprofessional review?
Frustrating as it is, this is something that happens to many authors at some point, and the simplest solution is to shrug and move on.  The editor probably already knows that the review is sub-par, and has decided to move on anyway.  Arguing with the editor at this point is not just attacking the reviewer, it's attacking the editor's professional knowledge and judgement.  It's not impossible to have a good outcome from responding, but it's unlikely.  Even if you do get a positive response, the editor would simply send it out to a new set of reviewers, so even the best-case scenario has you starting all over anyway.  Find a new journal and send it there.  

That's assuming that the review is genuinely completely useless.  From your description, I'm not convinced.  The reviewer may be wrong, but it doesn't sound as if their process is completely wrong; there is a specific reason for the rejection, it is based on something in your paper, and the fact that there is empirical support doesn't seem like a strong argument in your favor. Before you resubmit to another journal, you should seriously consider how to deal with that issue.