The commenter's point isn't that philosophers generally endorse dualism, it's that even those who claim to be monist materialists, etc. tend to possess latently

The commenter's point isn't that philosophers generally endorse dualism, it's that even those who claim to be monist materialists, etc. tend to possess latently dualist assumptions or conceptions of what consciousness is. Chalmers in particular pokes at this issues and challenges physicalists to either totally reimagine their understanding of the mind (cf. Dennett among others), which is mired in semantic and other difficulties, or perish. Moreover, dualism is certainly no longer dying (or dead)—this is confirmed both by reading the literature and surveying departments. It's certainly not as unusual as it once was.