When I think older men starting families just look at the celebrities having kids around 60 plus. Tony Randall, James Doohan and now Steve Martin. The problem is two fold as I see it. The first is financial. Why should a child suffer the financial consequences of an old guy's desire to be a father again. Let's face it the older you are the closer you are to the end of your working and/or high paying career. Throw in a catastrophe of any kind, medical, home, lawsuit etc all of the sudden the new family and children are put through hardships that should'nt have been.
The second IS age. Why should a young child, teenager or even young adult be put through the trauma of having a older parent get sick or die. The older parent might do fine the first 10 years or so but what happens to the child's mindset if their parent gets sick or dies at a critical time in their life. Even if sick should the child be burdened by trips to the hospital when in fact the parent should be burdened with trips to parent teacher conferences, a child's athletic event, play, dance etc. It's called childhood not old farthood.
To me a parent should be able to easily see their child through college, their first job, apt/home and kid. Any of these things could be affected simply by having to deal with old people problems and issues as a kid.