I do accept your points @LonginesPrime that ideology is a more accurate way to describe what we are seeing and experiencing but it is a word which can be perceived as carrying negative connotations.
Sometimes, depending on who I am discussing with, I want to use a softer term than ideology.
Sometimes I will say gender identity/queer theory because the two are distinct but often found together, particularly in institutional capture.
That a good point, PomegranateOfPersephone and I absolutely agree that a crucial part of being able to discuss this stuff and encourage people to perhaps consider things from a different perspective is knowing your audience.
And as FemaleAndLearning points out, people who see gender identity as fact can get very upset hearing it called a belief. I can see how this is probably partly where the notion that we are trying to deny trans people's very existence comes from, because I'm coming at it from the perspective of "you believe what you believe and I believe what I believe and we should be able to respect each other" but they tend see it more along the lines of "I don't believe the way you live your life is valid and you're just plain wrong". I think that because they don't realise it's a belief system, they take my lack of belief as a direct criticism of their life choices.
I can absolutely understand why someone who's made irreversible medical decisions for their own body or that of their child desperately needs to stick to the idea that gender identity ideology is a scientific fact and not a belief. I can't imagine the internal conflict a trans person or parent of a trans child must experience once they start to entertain the question of whether gender identity ideology might be just one of many ways to interpret the human condition and deal with psychological distress, and that there might be other feasible interpretations of the situation that don't require the interventions you believed (or were told) were absolutely medically necessary at the time.
There are certainly times when I find gender identity is better described in less explicit terms to ensure people will continue to listen (or to avoid people misinterpreting your words as hateful because they have been led to believe such terms are intended as hateful). And I think that discussing it with parents of trans kids or with trans people themselves does often need to be handled far more sensitively than the way I might speak about gender identity ideology on MN, or in a hypothetical debate or in a response to a government consultation or in legal documents or in other more formal settings.
In general conversation, I sometimes say "I don't believe in gendered souls" and then let the other person explain how it's not a soul in the religious sense, and then I just curiously probe what they actually mean (in an effort to genuinely understand their thinking, not in bad faith or to trap them or anything), and ask them how I, as a non-believer in souls, am supposed to reconcile my belief that souls don't exist with a belief in an inner sense of gender that sounds very much like the description of a soul from my Christian upbringing. It's not physical but it's more than simply a medical or psychological phenomenon; it somehow transcends the physical and the medical and psychological, but is not spiritual in the religious sense, so what exactly is it, and why don't I perceive it in myself the way they do?
It's always an interesting discussion and I've never found that anyone I've said "I don't believe in gendered souls" has taken me to be trolling them or trying to be hateful. I'm just trying to understand their position and to explain to them why mine is different.
Like many of you, I'm very happy to discuss people's individual beliefs on gender identity with them and while obviously gender identity ideology is alarming and extremely dangerous for lots of vulnerable groups, I also find this whole movement absolutely fascinating from a human perspective - not just in terms of the psychological and sociological aspects, but in terms of the political and legal issues, philosophical and religious issues, the various economic factors, the advancement of medical technology, linguistic power, the lot. It's terrible, obviously, and my heart goes out to everyone on all sides caught up in this in various ways. But it's also incredibly interesting and valuable as a study of humanity.