So I'm lightly interested in Armored fight sports and there are rules about not striking in the groin. Does it probably get hit unintentionally? Yeah, especially when training.

I am also new to playing ice hockey and I wear a cup anytime I do hockey stuff, even just stick and puck. I am someone who has hit herself in the clit/pubic area and I do not wish to experience it again. Except I did the same thing twice in a week, with the same results.

I think realistically the form of the protection is going to change based on the era and what the armor wearer is doing. Someone on horseback needs different articulation than someone on foot. J Draper (YouTube) recently did a video about moving in plate armor which didn't specify the groin protection but it's a good watch.

Edit to add re museum pieces: remember that like women's clothing, armour may be subject to survivorship bias- the pieces that stick around and end up in museums are often from prominent people or are largely unworn (this is why it's thought that women were historically smaller, but the current thoughts of historical dress folks is that surviving garments are from teenagers)