Think of it as game theory. If you are in a card game--poker, bridge, whatever--and you don't like your cards, you are okay with starting over and re-dealing. Or, from the jury trial world, if lawyers think they are losing, they will try to cause a mistrial, so as to start over with a new jury.
When liberalism approaches radicalism, the base mindset is that things are "so bad" that "anything" would be better, especially if they get to control the change. They see all of society, all of the centuries of progress (especially in the west) in feeding, clothing, housing people--not just that but prosperity--and in providing laws, constitutions, social mores, freedoms, opportunities, etc., and they think that on balance, any change would be an improvement. They focus on the glass half empty 100% of the time. Social injustice, income inequality, privilege of families successful from previous generations, wars, failures of the healthcare system, etc. By focusing on the negative all the time, they come to believe truly that "anything" could be better.
I remember a saying in my family whenever someone would say, "it can't get any worse," the response would be "yes, it could be that plus a poke in the eye with a sharp stick."
Many liberals actually want to make improvements to what already exists, but usually they are weak-minded people without a comprehensive worldview. They just attach to any proposed idea of improvement without a full consideration of the costs of the change. The worldview they do have is mostly atheistic, so their hope for any positive in the world usually looks to government or media as the path. The problem is that the radical liberals who do have a comprehensive worldview believe--or act like they believe--that the first necessary step to get to the new better world is to burn down and destroy everything that exists now in society. Basically, a Marxist mindset. (Now, whenever and wherever Marx was, maybe the society actually needed to be destroyed as the first step, I don't know, but I definitely don't think it applies to 2024 USA.) So, being the only liberals with a comprehensive worldview (a terrible one, in my opinion), the burn-it-down Marxists have a great influence over the let's-just-make-things-better bleeding hearts on the left.
So, on an issue like gender destruction, the bleeding hearts are persuaded by the "let's just make it better for the poor gender dysphoric kids who are being bullied," but the evil wizards are leading them with a goal of destroying Christianity, families, and other social structures that they feel are in the way, long term, to implementing a better social(ist) structure.