To use a gaming metaphor that hopefully lands, the XP grind from level 1 to 92 in Runscape is the same XP amount as the XP needed to go from 92 to 99 [0].
It is also illustrated with the Pareto Principle and the 90/10 rule where the final portion takes the most resources. Someone can easily become top 10% basketball player given the right training. 27M people played basketball recreationally in the US in 2021 [1], you only need to be in the top 2,700,000 players to be a top 10% player. There's only about 500 people in the NBA in a given year [2] so they represent approximately the top 0.0018% of organized basketball players.
If you include people who play rarely or in pick-up games, the odds of a top 10% 5'9 player jump drastically. 5'9 isn't that short either, it's roughly the median height of an American man.
[0]: https://runescape.fandom.com/wiki/Experience/Table [1]: https://www.statista.com/statistics/191632/participants-in-b.... [2]: https://www.hoopsbeast.com/total-nba-players/
Do you get more XP on average when you're a higher level?
Sure, if you count everyone who's ever touched a basketball in their life - it might not be hard to be in the top 5%.
If you counting anyone who has played at least within the last 3 months - it's not going to be so easy.
Try being in the top 1% of basketball players if you're under 5'9".
Easier said than done.