I've been thinking about social constructs a lot and doing a lot of research into them, and I've basically come to support the idea of constructivism: that essentially all of reality is a social construct, and that everything only exists through our subjective experience of it. That even science itself is our constructed understanding of the physical world, not the physical world itself. That basically everything new we experience is manipulated by the context of our own previous experiences, which is both shaped by and shapes our understanding of the world.

I think this understanding is important, because it disproves all arguments that essentially go "that's just the way it is", or otherwise try to root themselves in alleged objective truths about the world. For example, transphobes have used sex (as opposed to gender) as "objective" so they can argue about fairness in sports or some other transphobic bs. But our definition of sex is just as subjective - socially constructed - let alone any notion of fairness in sports being at all objective.

But on here, with everyone talking about materialism vs idealism, it sure seems like constructivism is the same idea as idealism, which Marx et al argued against. I've read through the prolewiki pages on idealism and dialectical materialism and it seems its just the part about objective reality that I disagree on. e.g. I agree with all but the first bullet point in the list in the introduction of https://en.prolewiki.org/wiki/Dialectical_materialism.

To put the sex and gender example above in idealist vs materialist terms, I think my understanding is that an idealist would argue that sex and gender are subjective, and that by changing our ideas about sex and gender we can make material change on things like trans rights. A materialist would argue that there is an objective natural phenomena that we refer to as sex, but that that phenomena is in constant motion and by guiding that change we can change our ideas of sex and gender. To me, the idealist just makes a lot more sense here, but I'm frustrated by that because apparently Marx considered materialism a foundational theory for leftist ideologies, and I don't know how to reconcile this.