Not a NodeBB specific test, but a NodeJS one, and just an isolated example, but suggests that Node at least is far faster on Linux. Now keep in mind this is old so pretty much worthless as a test. I'm interested to do some real testing, though.
Hey we over at growshows dot com formely. talksmoke dot com are looking to hire a full time NODEBB forum professional to edit our forum install new designs or possibly even ones willing to make custom ones, we are looking to start out with moderate pay and as we grow even though we are actually really big before we switch we will see how this goes but need a mackover and a team member always around to help and we will pay of course contact over email