If you flip the argument on its head you can frame it as: since most objects die young it's very likely they will stay on the stack and thus it makes sense to i

If you flip the argument on its head you can frame it as: since most objects die young it's very likely they will stay on the stack and thus it makes sense to invest in an allocation-site optimizer that will put the object on the heap only if static escape analysis says it may escape the lexical scope.