I don't think that's really a measurable objective. They might agree. We can see how far progress towards women's rights has come, but the only metric a religion can use is Sunday mass attendance if they want to figure out how many souls they're saving.

Feminist ideology allows itself to be reformable, there is no prescription against that. See now the problem with immutable ideologies?

Those ideologies aren't immutable though. They claim to be, but they're not. Otherwise the denomination of Reform Judaism would be an oxymoron. And that's my point---all these religions have changed. Since Judaism clearly still exists in the world, and essentially 100% of Jews do not follow the Torah's proscription on killing your whole family, then we are forced to conclude that Judaism, despite its claim to be immutable, is instead reformed. The only other option is to say that Judaism no longer exists which is ludicrous.

Which only shows the weakness of your approach, of insisting that votes, [and not the meaning of the ideology, and its prescriptions, and the degree to adhering to those] should decide if someone does actually subscribe to an ideology.

No, that shows the strength. The only other way to determine whether someone adheres to the ideology is to determine the tenets of said ideology, determine which of those are breakable and which are not, and then go down a checklist of beliefs and see if that person adheres to them all. But nobody's ever going to agree on the checklist. For example, you've implied that adherents of religions that believe their holy book is the literal and immutable Word of God are only adherents if they abide by the entire book literally. That would mean that there are very few adherents of any religions---even Muslims considered hardline from our perspective like Iran plainly violate parts of the Quran.

You wouldn't call a scientist someone who doesn't apply the scientific method in their field of research.

You wouldn't call a moral person someone who severely breaches current moral norms.

You wouldn't call a feminist someone who argues against women's rights.

Nor would anyone else. Do you honestly think my method would identify non-Muslims as Muslims?