Not true! My 21-year old son has been through the whole TOS, much of TNG, all of DS9 and STV, but only a little of Enterprise. That's much more than I can say. We watch Discovery and Picard together. We groaned through much of the Discovery, but Picard, while not perfect, has been a lot of fun so far, mainly I suspect because its a simpler tale told at a more leisurely pace, which allows the characters to breathe.
His real area of expertise, though, is Dr Who. I'm talking JoeP levels. Not new Who, which gets short shrift, but vintage Who. He starts to get a bit sniffy once it moved to colour.