I wonder if it's even more broad? They aren't actually upset about an old edition of D&D or an older game; they are upset that those days are gone forever.
I remember when The Isle of Dread was the "cool new thing," and I remember when I was the "cool DM," and my friends couldn't wait until the weekend so that they could come over to my house and play for hours--but now? Mystara isn't cool anymore (in fact, I've learned it's rather problematic), my teenage nieces and nephews think I'm an old dork (because I am), and nobody comes over to play D&D anymore (we're on VTT now).
It's bittersweet for me, but I think that for some folks it's mostly bitter. Growing old is uncomfortable and change is scary, and it's hard to make friends as an adult. I think some folks are really struggling with that.