I think an active person, especially one who is engaging in a fair amount of resistance exercise, will require more calcium as their bones strengthen. I couldn't tell you how much that is but I take 400mg of Ca and Mg every day, but I'm thinking about decreasing that to 200 of each because I have my doubts about whether I need that much. As far as those who take too much, someone who is consuming sufficient amounts of D3 and vitamin K2 shouldn't really encounter soft tissue calcification. The average person who eats a lot of dairy, takes calcium supplements and gets little of d3/K2 is probably calcifying their soft tissue and dying early as a result.
A bigger concern for me is calcium blocking the absorption of other minerals, so I try to segregate it from high nutrient density foods like liver.
My gut feeling is that hunter gatherers get very little calcium and magnesium from their food and that nearly all of it comes from their water sources. Foods highest in calcium tend to have very little of it that is bioavailable. I read a study a while back that showed the bioavailability of the calcium in spinach to only be 5%. If I'm not mistaken, it was specifically the oxalate content in spinach that blocked absorption. On top of that, there are hunter-gatherers like the Hadza who (according to Marlowe) don't eat any vegetation. I doubt that the tubers, baobab, undushipi berries and meat/organs they eat have all that much more than our equivalents. They boil their meat, but obviously wouldn't have traditionally. I don't think humans during the Pleistocene were eating bone itself or eating enough egg-shells to really get that much.
The RDA just stinks of the dairy lobby, in my opinion.