I also believe that some personality traits are heritable. Shyness can be inherited. So can introversion and extroversion. So can being impulsive or contemplative. I also believe that the impulse for fight or flight is inborn and inherited.
I also believe that each of these traits can be exacerbated or moderated --or enhanced or evened out depending on a host of other factors, many of which are environmental and upbringing. Some environmental conditions might include exposure to hazardous substances such as lead or poor nutrition or lack of access to opportunities for socialization or education. Some are upbringing--an outgoing child can be encouraged in this tendency or discouraged, heavily. Introverts can be encouraged to find ways to be more comfortable engaging with others. They are still basically extroverts or introverts --and most of us are mixtures of introversion and extroversion. I've watched some pretty determined people attempt to force an introverted child to be more extroverted--which did not work. At all. And, imo, only drove the child to withdraw more into themself. Impulsive behavior can be moderated---children can be encouraged to develop patience and to be more calm and to think things through a little more. They may always still be impulsive but that doesn't mean they MUST always be out of control impulsive.
Some children are more inclined to be physical, to express their feelings physically, to run, jump, climb--and sometimes to hit or push. Again, these behaviors can be modified and channeled but more physical people are more likely to always be more physical. This is not the same thing as saying that violent behavior is inherent and cannot be moderated by how a child is raised.
Even sociopaths can learn appropriate behavior, even if they never feel things the same way that other people do. They may choose to behave in a certain way that others find more acceptable because being accepted benefits them compared with how most people operate: treating others well out of empathy and sympathy.
Yes to all of that. You might notice I snipped out the free will bit before saying that. We don't need to get into that and in any case it's intractable.
In a nutshell, things can be learned. Whatever nature provides, it can be moderated to some extent, including deliberately, by, say, parents. And between the birth of a child and for a number of (crucial, formative) years after, parents can have an enormous influence, usually way beyond any other 'environmental' influence. So one way to approach the issue would be to encourage parents not to impart or encourage traditional gender roles. Obviously, I am not in favour of children being brought up to conform to traditional gender roles.
But even that can be tricky. Upbringings do not take place in a social vacuum. By that I mean that a parent might think to themselves (about for example their infant boy) that he will soon have to enter the world of boys (and men) and.......well, that parent won't want their boy to be the one who the other boys pick on. And so on. In other words, I think at least part of the reason parents make gender role distinctions for their children is because they are trying to best prepare them for the real, gendered world and not some ideal one where gender doesn't matter.
Obviously the best approach, as with most things, will involve balance and nuance, and attention to the needs and characteristics of the particular child and the particular situations and so on. For example, a parent bringing up a boy in a rough or deprived neighbourhood has certain things to consider that a parent in a more affluent, privileged neighbourhood might not have to worry about so much. I doubt there'll be a 'one size fits all' set of solutions.
It may be that this is what the writer of the OP article was doing when as a father he literally shut the door to his small son. That's certainly an interesting (and poignant) example. As a parent of a girl who found herself in a similar situation with a clique of girls and sometimes came home in tears, I empathised. The OP article writer's question, to himself, about whether, by making his boy 'toughen up', he was reinforcing unhelpful, 'boys don't cry, they man up' gender roles, is a good one, I think. The writer himself seems to have at least some minor regrets along those lines. It might also be that the writer felt that it was his job, as a dad (and not a mum) to impart the 'tough love'. Which of course is often the way these gender roles make their way from generation to generation, the writer himself having been influenced by what he learned in his own life and upbringing, and so on and so forth.
In all of the above, I'm speaking in very general terms, obviously.
