When they start trying to wield the class hierarchy against you, I find it useful to start using infantalizing language, and to specifically characterize them as an out-of-touch class minority. It's not going to "gain traction" or anything -- if you pull this on reddit or other lib-holes you'll eat a bajillion downvotes or whatever -- but it does fucking irk them if you challenge the notion that their perspective is inherently more rounded or complete.