I'm with you dude. And similarly, I'm not that old either (33), a lot of my friends and I still make old ass Simpson references to new stories and shit going on so we're sorta guilty.
But I think its more than just "humor", its how some people interact now; whether through sharing experiences or even insulting each other, there's no originality and people praise those who are best recalling jokes.
I always thought it was weird how "i fucked your mom" was the go-to insult in gaming. Practically everyone has heard it, and people were still using it as though it was offensive or demeaning. Its sad at a certain point, where all you have to say is unoriginal repetition and to think that others are impressed or offended or whatever you think those words have on them.
A sort of extreme example: My wife and I were out taking the dog for a walk this summer and a young kid came upon us. He was probably 9 or so, I'm horrible at estimating kids' ages. Heasked if he could pet our dog. The kid was obviously austistic to a certain degree and walked with us for a bit. We live in a small town, kid lives like 4 doors down from us, so not totally weird. But what I found totally astounding was the way he interacted. It was by reciting memes. Like he'd state the image, then the top text, bottom text. It was wild trying to relate to this kid, asking him about school or hobbies. After he took off all I could think was that he was like interacting with a live version of Reddit. I feel so bad for him because I can tell he's ostracized at school so he gets his interactions with others online, but he thinks that's normal interaction.
Is there a whole culture of people out there who have no original experiences and only live vicariously through online interactions? Go to something about livestreaming Lets Plays or something and watch people lose their minds about "experiencing" the event when something big happens. Take the recent CSGO tournament for example and find the threads full of "I WAS THERE WHEN IT HAPPENED" replies. I guess folks do that with sports too, I find it equally weird. Do they not realize that relating to others by stories of "have you seen this joke" is abnormal?