No, it's not that Matt's was superseeded by Saranac (same brewery, more upscale beer). And no, it's not that the original bakery has gone out of business as a retail outlet. It's the sudden appearance of two new "traditional" items on many menus around town, greens and chicken riggies.
My father, inordinately proud of SmallTown and various institutions and events around it, like the 'Munstitute' and the Boilermaker Race, started talking about these items as though they were around for decades. And perhaps they were, but not in any restaurant I'd dined in as a child. My sister confirmed that no, she'd never heard of them until recently, either. Turns out, they weren't part of the dining out experience until at least the late 80s when they moved from grandma's kitchen to restaurants.
That's not to say they are bad or that I wouldn't order them when visiting SmallTown. But they weren't part of my childhood. Sorry Dad.