Genuinely, orthopaedics is a very manual speciality, akin to carpentry.
To successfully correct many orthopaedic issues in surgery, the surgeon has to be able to lift and support limbs which are paralysed, relocate joints in sockets, which requires HUGE amounts of consistent pressure, the list goes on.
I don't think it harms an intelligent 3 year old to know that most orthopaedic surgeons are men. I really don't. It's the parent's job to then reinforce to the child that what this means, is that they would have to work especially hard if that's what they want to do.
I gave the example on another thread, but my DD1 (5.9) has SN which affect her globally. To put her needs in context, she goes to Special School, but is one of the more able children there.
She has consistently and reliably told me for over a year that she wants to be a 'farmer' when she grows up. Now, we don't know why yet, but she has a wobbly gait, weak hands, and a slightly week grip. We don't know what her future holds, but she is very unlikely to be strong enough to be a farmer.
For me, responsible parenting isn't to gloss over it all and say 'of course you can dear..', but rather to help her to moderate her expectations to a practical but aspiring level. So, I say 'well, you'd have to work very hard at getting as strong as you can, DD1. To be honest, I think your hands might not get strong enough for the big animals, but you could be a small animal farmer, and maybe just feed the big animals?'
A GP treating the 3 year old with respect, recognising her intelligence, and giving her an honest appraisal, is no bad thing in my view.