At this point, most of the pressure seems to be coming from a combination of peers and from within. In my daughter's case, it seems to be the girls not feeling comfortable in a techy environment - fear of being ostracized, as well as genuine possibility of being ostracized.
From what I've seen, the adults are all for her being involved. She's just another kid to them, as it should be.
First, congrats to your daughter for sticking with her interests and not letting others decide what she should be doing. That is an engineering hallmark and it sounds like she will go far.
Long ago (mid 80's) one of my co-op college summer interns was a bright young lady who was very interested in gaining some hands-on analog design experience. During her summer stint she took a week or so to accompany her immediate family on a visit to her ancestral country South Korea. When she returned she told me how her Korean relatives tried to convince her mother to get her out of engineering, "not suitable for a young lady".
Fortunately she ignored the well-meaning relatives and so did her parents.
You say it's not "socially acceptable" for her to be techy. Where specifically is this social pressure coming from? I assume in this day there are no adults telling her she shouldn't be interested in robots because she's a girl, or are there? Are the boys behaving like she doesn't belong because she's a girl? Do her female peers maliciously alienate her because she likes robots? Or is it no more than that she feels awkward being the only girl? In that final case the "social pressure" is coming from within her rather than without.
I'd say there's a huge social factor here. Certainly more so than any capabilities issue. My daughter has been involved in the FIRST robotics program for the last four years now. The first few years, the boy/girl ratio was about 50/50. Each year it's gotten more skewed toward boys to the point that she's now the only girl in the program here in her grade level.
Based on discussions with her, it seems to be as much of a social pressure as anything else. In many places today, certainly in many schools, it's socially acceptable for a boy to be a techy, but not for girls. Fortunately, my daughter is sticking to her interests and not succumbing to that pressure.
I hear a lot of talk about making sure the education system tries to welcome women into the tech world, but we need to do a lot more to get society welcoming both genders equally into tech. I suspect that a lot of potential female engineers are diverted from that career path in Jr High School, and that's a shame.
I think women are more interested in mastering the social world than mastering the physical world. That's not a criticism. It's practical. Engineering is a very physical thing. There's a lot more testosterone to it than some people recognize. Good engineering is a lot of "idea Darwinism" i.e. creating a lot of ideas and then shooting them all down and then going with what survives. It seems women often take idea confrontations personally whereas men can treat it as just part of a process.
I have three daughters and one son. In spite bring your child to work days, home projects, experiments, and demonstrations, applied engineering (DIY home projects, auto/motorcycle mechanics, tuning, etc.), NONE of my daughters have shown the slightest inclination of pursuing any kind of engineering career. My son, no problem. Although, he prefers to work with his hands so he will probably excel in the trades. This thing of trying to up the female ranks in engineering is like trying to get men to go into hairstyling. Sheesh.
It's not just about role models, although this is factor. It's also to do with the way we bring up our boys and girls. Preferences are often made from an early age.
PS. I am all for diversity in all walks of life, and this should work in both ways.