I think I will refuse to fly with any FO younger than 30. Now that we old buggers can fly on until we are 65, we don't need all that many new pilots any more so I suggest a minimum age of 25 before an ATPL is issued.
On a serious note, I always wondered how one day could make so much difference to one's ability to do your job. You land at 2359 and then 2 minutes later you are too old to work. Does that seem sensible?
At long last, common sense prevails. I for one will be pushing for fly until your medical expires!