The main reason for not jumping down very far is the repeated jarring of the landing can result in issues like arthritis. This is a bigger risk in larger birds, in long lived birds, and if your bedding is thin or otherwise less resilient.
Mine roost is about 5 1/2 feet above the floor. I usually have a full foot of particularly bouncy bedding (mostly dried lawn clippings and dry maple leaves, some pine shavings, general forest and garden debris). I can see the bounce when one lands.
In a perfect set up, I might try to have lower roosts but I have only just enough space so it is more important that they be able to use all the floor space.
They have a platform part way down. Sometimes they use it, sometimes they don't. It seems to me they use it only when it is in the way to where they are going.
If I replaced layers every year or two for other reasons then how high the roost is would matter less than if I wanted to keep these hens as long as they are healthy.