So the thing about Morrison's work is he is very, very cognizant to draw from basically all eras. The dude loves picking and choosing the best aspects of characters from myriad writers. It is one of the best things about his Superman, as it is for his Batman. I just don't see how Morrison's writing is some counterpoint to my statement. Morrison revels in the myriad continuity and character changes.
A lot of then fans didn't like Morrison's Superman because it wasn't New 52 Superman, too. Rebooted to the same old status quo. I'm sorry Rebirth was bad for you because it didn't reboot Superman again. But I like Jon, so it was cool for me. Then again, I liked Chris, too. So it wasn't really a full nostalgia bomb, as we never really did get Post-Crisis Superman's son. It wasn't even nostalgia...it was just new. All they did was skip Clark and Lois' relationship building back to Pre-Flashpoint levels, honestly. And thank goodness for that because that is an over told, and well told, history. Didn't need part 20 of it.
Jon Kent is not nostalgia. I'm not sure how you even came to that idea. We barely even got any of Clark and Lois as parents, either, in the old continuity. Relatively untread ground. Honestly, what nostalgia did Superman play to that you're miffed about, anyhow? The more I think about it the less I acknowledge your point.