About the Left, someone famously said (but I can’t remember his name): “They never quit. It’s like mowin’ the lawn.”
http://townhall.com/columnists/patbuchanan/2014/10/21/the-price-of-papal-popularity-n1907736/page/2
In his remarks at the synod’s close, Pope Francis mocked “so-called traditionalists” for their “hostile rigidity.”
That is one way of putting it. Another is that traditionalists believe moral truth does not change, nor can Catholic doctrines be altered.
Even a pope cannot do that.
Should such be attempted, the pope would be speaking heresy. And as it is Catholic doctrine that the pope is infallible, that he cannot err when speaking ex cathedra on faith and morals, this would imply that Francis was not a valid pope and the chair of Peter is empty.
We would then be reading about schismatics and sedevacantists.