It doesn't matter how outlandish a liberal innovation might seem, if it fits with liberal principles then it will be pushed onto society regardless - if, that is, there is no effective opposition to liberalism itself.
Here's an interesting example. There is a push on now to have people accept the idea that men can give birth to children. It is beginning to become politically incorrect to talk about "pregnant women" as this excludes women who identify as men but who nonetheless get pregnant.
Seems kooky, but look at the following Facebook thread:
This is a debate between radical feminists who insist that you need to be biologically female to be a woman (they are called "terfs") and other leftists who reject this as "transphobic."
The significant part of the debate is that a professional organisation for midwives (the Midwives Alliance of North America) has already committed itself to the idea that men can give birth ("suggesting that only women can give birth is not welcome here").
The midwives association repeated this view in another thread:
The "terfs" who insist that being a woman is based on biological reality are warned by the midwives alliance that "comments that say that men can't give birth are transphobic and will not be tolerated."
There is so much that could be said about this. The twistedness of liberal morality is apparent in this discussion. Liberal morality is built on the idea that we should be free to choose our identity and our own subjective goods, but that we should allow others to do the same. Therefore, there is no objective moral order for individuals to orient themselves to, but instead the point of morality is to show how tolerant you are of others choosing as they will.
But it all gets mired in a contradiction. On the one hand, if a woman declares that she identifies as a man you are supposed to be tolerant and accepting of her decision to identify this way. But this then means that someone who points out, as a basic fact of reality, that there is a biological aspect to being a woman, will be told curtly that their speech will not be tolerated. So a morality of "tolerance" ends up being, by all previous standards, remarkably intolerant.
You can tell that if things go as they usually do that the terfs will lose this battle. If, as per liberalism, we are to be free to self-determine our own identity and pursue our own subjective goods, then it is difficult in principle to say to someone biologically female that they can't identify as a man and become a "pregnant male." To oppose this is, in liberal terms, bigoted, prejudiced, phobic, hateful, discriminatory and all the rest of it.
In the past, the only opposition to the liberal left came from the liberal right (the "establishment conservatives"). The liberal right would sometimes initially oppose these kinds of things (as "going too far") but once they got traction, then the right liberals would fold and would eventually end up defending the new status quo.
It's interesting now to see something different emerging. There's a section of the alt right which is now doing what a genuine opposition would have done decades ago, and actually push back in a determined way against the left liberal project. It is still too small to win in the wider society, but it is carving out a political space where the older dynamic no longer runs as it used to.
So perhaps we won't see, in a few years time, a liberal speech code outlawing the use of the term "pregnant woman" as hate speech. Maybe the usual pattern of politics will continue to lose ground.