Horses for courses I suppose.
But saying someone is 'ready' is as if not more arbitrary as anything age based and no system is perfect. In fact 'ready' is far more subjective. In fact the majority of the examples I cite are where someone thought they were 'ready', convinced them to take a command and after 18-24 months they've binned it, which just throws the sqn into disarray while someone tries to convince someone else they are 'ready'.
While what you say about the family element is true, many people by that point will be at a point where they can know better if they are more able to commit to the role. When I took the reins the sqn, staff and CWC, knew fully what they would get from me and as my kids got into their teens I was able to do more. For several years my wife and kids came to sports competitions, parades and public events that the sqn did. But I suppose that'd be seen that as wrong.
You constantly see young officers going in promising lots and then finding it doesn't fit as, jobs, changes of job and or new / burgeoning relationships 'interfere', and then pack it in.
It is a worry that we are so very dependent on cadets transitioning and staying and then wanting to or being cajoled to take on command roles and then burn them out, to see them leave (a number via NEP) and never come back. When I timed out three of us (not all the same sqn) stayed and two of us are still doing it.