This is all about circumstance.
Elton didn't meet David until late in life, so why should he be denied the chance to be a father? He could well have had a child when he was married to Renate, but it would have been a bit of a fluke, and a band aid child too.
Nonsense. Elton has been with David for twenty years. If parenthood was such a pressing commitment for either of them it could have happened when they were both young enough to see a child through to adulthood. This isn't about 'circumstance' but the choices they have made.