Going by year alone you appear to get two answers. But if you assume they win at the last (max) date of a Grand Prix within that season you can calculate the difference in days... and indeed Vettel was 165 days younger than Hamilton at the time of winning.
Once again a great challenge, and once again I am miles from the podium 🏁
Also I will not blindly concur to the result, since my first calculations found another young driver, but here it is
Got a bit stuck when I kept having Hamilton as youngest winner (not biased at all) until I realised that the points were cumulative throughout the season. Enjoyed the challenge, looking forward to seeing how other people completed this in a faster way!
So as it turns out:
Sebastian Vettel-8546 (Days Old)
Lewis Hamilton-8723 (Days Old)
Vettel was 177 days younger than Hamilton...
-This assumes the season on 11/25 of the year as that was the season end for 2018.
This one took me a while to figure out as I kept getting Hamiliton until I used the DateTimeDiff and then used "Days" versus "Years" on the sort, while carrying both through until a Select at the end, I also had to change the VW String to an Integer...
This was an interesting Challenge, as I used Summarize twice, once to get the cumulative point totals for the years of racing and then again to get the Maximum amount of points (winner) and then used a Join to get the winner, almost like a filter.