Clark (real Superman) is currently off-world, dealing with a crisis which, according to Jon's time in the future with the Legion of Superheros, is what kills him. Jon is "filling in", acting as Supes on Earth, "until Clark comes back."
BTW - As an aspiring reporter, Jay was more impressed that Jon was the son of Lois Lane
Jon is basically a new character - he's existed since 2015, but until very recently he was a child, but he got aged-up as part of a storyline. So at least people can't complain that a longstanding character with previous relationships has been gaywashed. Tim Drake, the third Robin, was recently turned bisexual as well. That makes less sense, as he's had plenty of girlfriends, and there hasn't been any indication he's into anyone else. BUT despite existing for longer than me, the character is 17ish, so it's not unreasonable that he just "didn't know" until now.
#DCfanboy
Spoiler:
Fu
ck sake, it sounds like I know them personally or something