Lisa's bewilderment at being the only sane person in her town is this show's most overlooked comedy resource. Her blank stares and general exasperation make everyone else several times funnier.
She could in the past, though it required a bit more effort on the part of the writers ("It's okay, that isn't your fault, it's a bird thing. You don't control the birds. You will someday, but not now.") But now all her scenes suck. Which is also true of everyone else, of course.