You're reading this badly, and it's only going to lead to heartbreak. Either ask him outright, cards on the table, or just leave it.
People do sometimes just have flirtatious personalities, even concerning the genders and sexualities they aren't into. I do, depending on my mood. He doesn't even know you - or that you want to transition, right?
People often do generalize and say 'men/women are a waste of time, never again' after a break up. They don't actually mean it.
Of course he wants to maintain contact - he thinks you're his friend and potential housemate.