I'd call it a ravioli.
Either way, if you define calzone, (or ravioli), as "a dough filled with something, and then sealed" then yes, I'd say a pop tart is a calzone.
I'd generally say no to all these "is a hot dog a sandwich" etc questions because these foods are all culturally dependant. A calzone is a calzone because it's made based on some Italian recipes (I'm saying plural because each province has their own recipe, you know how it is in Italy, but obviously a calzone is something we all recognize as an Italian thing). And you can tweak it how you want but at some point it differs from the original recipe so much it's not a calzone anymore.
Like, the more I cook, the more I realize that pretty much all cultures have *some* variation of: dumplings (with filling or plain), noodles/pasta, sweet and savoury pies, hearty comfort stews, flatbread, and probably more. And very often, especially with things made of dough, they're made quite similarly because people arrived at the same conclusions as to how to best make the dough. Should we call all those the same? No, because the differences are culturally important and it's not just about the shape.
Either way, if you define calzone, (or ravioli), as "a dough filled with something, and then sealed" then yes, I'd say a pop tart is a calzone.
Like, the more I cook, the more I realize that pretty much all cultures have *some* variation of: dumplings (with filling or plain), noodles/pasta, sweet and savoury pies, hearty comfort stews, flatbread, and probably more. And very often, especially with things made of dough, they're made quite similarly because people arrived at the same conclusions as to how to best make the dough. Should we call all those the same? No, because the differences are culturally important and it's not just about the shape.