Manifest heretics leave out the guesswork and according to Catholic teaching, manifest heretics are not Catholic and therefore not members of the Catholic Church.
It really isn’t that complicated.
It isn’t complicated for those with an honest desire to know, anyway. Heavens, there’s been reams written lately about papal authority, where it extends and where it doesn’t. In what circumstances we can criticize the Bishop of Rome and in what circumstances we must obey.
Not that we’ve solved the issue entirely, but when people get on and bloviate without showing even a modicum of awareness of the factors involved, it gets a tad annoying.