Scoring in the NBA is waaay up so far this year. Maybe it's just an early season thing, with teams not expending as much energy getting back on defense, but it really looks like there's A LOT more emphasis on the transition game.
For a quarter century, the NBA has been playing at what would have been, by the norms of the 60's through early 90's, a very slow pace. If you look back at 1988, the average team scored 108.2, despite only averaging 1.6 made 3 pointers a game. Last year was the highest scoring season since 1991, but a lot of that increase is due to made 3's (which hit 10.5 per game). The next trend appears to be to combine the 3 point bombing with an emphasis on getting out and running (the Golden State model, as opposed to Houston).
If that's the way the game keeps going, Diallo has a bright future in the league. He'll probably never be a knockdown shooter, and his overall skills are dicey for a pro, but he is an absolute beast running the floor, and has all the physical tools to defend 3-4 different positions.