Don't worry about it too much, just egg_irl/traa humor, lots of them like to poke fun at the idea of turning people trans but it's a joke (it's meant to be a joke, though sometimes people violate the prime directive and it becomes not funny anymore).
Nah the worst is when you don't find it relatable or even understand any of it and people insist you do and poke fun at you (egging) sometimes going a bit too far, that happened to me. Wasn't fun, but I did eventually figure out about being Agender (and Isogender) which really cleared up the mystery of why I don't understand gender. Just kinda wish people didn't try pushing the stereotypes so hard on me, was real frustrating and uncomfortable ya know.
Btw I know I'm replying to old comments, been gone for a while and trying to catch back up.
I think the best thing is to be there for them if they want to talk about gender issues but don't be pushy about them coming out as one way or another. People will figure themselves out at their own pace. Suggesting the idea of possibly being trans is okay but it shouldn't be pushy, if it doesn't feel right for them it probably isn't right for them, at least at the current time.