Technically the answer is "everything", because the first time a major competition is run the winner is simultaneously the youngest and oldest person to ever win it!
But if we're going to rule out that there's still at least one additional case:
W Series - The all-female motorsport championship ran for a total of three seasons (2019-2022) and all three were won by Jamie Chadwick so she was the youngest winner in 2019 and the eldest in 2022
I think Birgit Fischer counts too - having won Olympic canoeing gold medals at 18 and 42