OP,
you are spot on with your observations. Many runners, with their almost obsessive passion for their activity seem to forget that their are other components of fitness which are equally if not MORE important for improved mortality and healthy ageing than their preferred activity.
With runners it is often the case of putting all their eggs in one basket.
Also it is automatically assumed that if one runs, one races. Why? Probably down to media and marketing. Running for enjoyment and relaxation on trails in old shoes for a few miles and mixing it with walking probably won’t sell too many expensive, modern carbon running shoes.
There is also the argument in recent years that too much running can be detrimental for many, and the stacking of too many miles over time will catch up to some eventually. This makes sense if you view exercise like the medicine some promote it as being. You can overdose as well as under dose, but this is an individual thing, as some can tolerate more than others before breaking down, one way or another. Unfortunately we never know where that line is until it’s too late and we’ve crossed it.