He was replying to your “Linux users would not pay for Cubase is invalid, as they would have paid for the license already.” remark in a rhetorical way.
Linux would of course increase revenue, but it may not increase profits. I don’t know how hard it would be to port Cubendo but i’d love to see it, they’re already releasing the same patches for Mac/Win so they’ve got a framework there to build on - i’ve tried Linux for audio for years and years, and still waiting for the plugin support and DAW that suits me to come along in Linux, it’s close, but i can’t make the compromises at this point in time.