Personalities aren't determined by age. Some people need to be coddled/built up to perform, others are Jalen Brunson.
Sane did lead the team in sprints in our last match, and against the US it was Leroy & Kai threatening to get in behind that caused their defense so much panic in the first phase of that match. Leroy also stretches the defense so Flo, Jamal, and Kai can drift around between him & Brown.
Now I do think that Leweling or Havertz could do all of that and even if their first touch is a tick less incredible & they are a tick less explosive, their better decision making and more reliable end product would make either one a better option on the right.
But Leroy does some very useful things for the structure even when his play in the final third is more like it was against Curacao than against the USMNT, and his touch/burst are on an even higher level than Jamie or Kai's.