I think that's part of the point actually. Clark never meant to change the world the way he has. He wanted to make a difference, help humanity find the future he saw with the Legion, but he never intended to become the symbol he did. He's not selfish of self-centered like that. But there are things beyond even Clark's control and I think this is one of them. And "Superman" and what that means has grown beyond one nice man trying to help people in his spare time. He's part of the cosmic clockwork (to make a Doomsday Clock pun). I think the universe keeps time to the movements of Supermen.
Clark would be fine with it, absolutely. I think it'd be one of the proudest moments of his life.Then there's the fact that Clark wouldn't be at all mad if Jon came up to him one day and said "so I was wondering if you'd let me call myself Superman now that I'm almost 30." Clark being Clark would likely say "honestly, I was wondering what too you so long." Clark's about the deeds. And it's not like Jon would realistically want to be called anything but Superman when he's old enough. Much like Damian he's basically counting down the days till he's old enough to share the name. If you read Super Sons then you know that the one thing that's never in question is if they want the titles. It's a given.
I think it can, but I think there needs to be more to it than "just" that. I think a new Superman should bring a major social shift with it. The change of a Superman should be sort of like the shift to the Industrial Age or the Digital Age (much like how we point to Barry Allen's debut as the rise of the Silver Age even though there was a lot more to it than just one character). If Clark is the face of the First Age of Heroism, the next Superman should (will) be the face of the Second Age, and that should be a big, world changing moment.I don't know why the coronation of Jon Kent taking on the official title of Superman Secondus can't be a huge thing. Why can't it be accompanied by a big adventure or assassination attempt?
I think we basically want to see the same basic thing, but our timelines are different and we're looking at it with different scopes in mind. I want to see a new Superman bring a new Age with him (you know me and my Super-myth), and that's something to be stretched out some, whereas you're looking at it from the perspective of human generations. As usual, I dont think we're actually all that far off from each other in the spirit of what we're saying.