Modern social justice cultists repeat the mantra that gender is just a "social construct" (a few of them even claiming that biological sex itself is such a thing).
Gender is not just a social construct, of course, but even if it were, the question arises why it's a bad thing. They always use that term, "just a social construct", as if it were an undesirable thing to get rid of. But why?
As a social species, almost everything related to interactions between people in our society is a "social construct".
Crime and punishment are social constructs. We, as a society, invented both things, and are "artificially" applying it to ourselves. It's the reason why the vast majority of people, when they for example want something, don't just go and take it from someone else. It's the reason why people don't just go to a store, take whatever they want, and walk off without paying. Even in the mildest of cases, at the very minimum, it's universally considered polite to ask before taking something that's not yours (in a situation where it could ostensibly make sense for you to take that thing, even though it doesn't directly belong to you.) It's the reason why the vast majority of people don't go pillaging, raping and murdering (and even those few that do usually get caught and punished very quickly). The social construct of crime and punishment is a huge deterrent of crime (something that has been demonstrated many times in very concrete ways.)
Traffic rules and laws are a social construct. They exist to make traffic fluent, and to minimize the risk of accidents. They wouldn't need to exist by absolute necessity but we, as a society, came up with them in order to introduce some order to the chaos, to optimize the movement of people and cargo, and to minimize the loss of life and health.
Interaction between people consists of almost nothing other than social constructs. Language is a social construct. The way we communicate our ideas to other people is a social construct. Our choice of words and expressions, depending on the situation, is a social construct. The rules of politeness are extremely subjective social constructs, but they help us communicate, interact and cooperate better with other people.
Concepts like privacy and respect are 100% social constructs, which in theory wouldn't have to exist, but as a society we have decided is the best way to go. When you go to the doctor, for example, some privacy is to be expected; other random people won't be able to hear you explain your medical problem to the doctor, and the doctor is expected not to divulge this information to random people. (In some jurisdictions this might even be enforced by law.)
In short, social interaction between people, no matter what kind, consists of pretty much nothing but social constructs.
So why are the social justice cultists using that term as if it were something negative, something to avoid and get rid of?