"Y'know, I actually feel sorry for you/them" never means that. It's just a way of showing contempt and condescension while getting to look like a really good person yourself.
I can't remember when, and I don't think it was recent, but I have a sense I have used the phrase myself. Hopefully long, long ago when it still might have meant what it literally does. But stop using it out there. The jig is up.