Just look at the densities spanned by fruit, custard, and chiffon pies -- let alone the textures of cheesecakes, which, as I mentioned upthread, are really pies.
Even pie crusts are varied -- dough crusts vs. crumb crusts.
Pie does have meringue; never seen that on cake... Although it's not too late.
Some pies have more whole fiber texture, like chunks of apple, peel of cherry, grit of raspberry.
I don't like pie either (except wheat-gluten free crisps!) but I definitely like the filling. While graham and Oreo crusts are ok for wheat eaters, ordinary pie crust is usually awful. Even the best pie crust lacks something. So bland and dry, or oily. I think if I made pies, and if I ate wheat flour, I would sweeten the pie crusts like those pre-fab lunchbox pie turnovers, and put a glaze. That's it. All pie crusts should be sweet glazed. But I'll just stick with the filling only.