You're probably right, which further underscores GP's position. At least where I am there are zero elderly people or kids riding in protected bike lanes. Older folks simply do not ride outside retirement parks in any appreciable capacity, and children are ostensibly not allowed to ride outside their residential neighborhoods. I'm afraid that continuing to design infrastructure in favor of groups who have no interest in it will result in a whole lot of wasted effort without solving any problems.
They entire point is that these groups have no interest in cycling because there’s no infrastructure that makes them feel sufficiently safe. And the goal is to change that.