“Bad” popes don’t teach heresy. They may sin, but they do not teach the Universal Church heresy.
Since Pius XII all successors have been bad popes. A new religion was formed that has little to do with Jesus Christ and much to do with secular humanism.
The Catholic Church, that is the one that’s headquartered in the Vatican is NOT catholic, nor is it holy. Holiness went out the window with the tenets and rubrics.