Leaving the moped in the middle of the street, creating a hazard, is the problem. Had he stayed there he might have gotten a verbal warning.
That's the key. Maturity or Responsibility choose your word, he didn't display good judgement. The issue I don't think is the moped or the stupid racing, I believe its the evading responsibility (simply removing the bike from the road and perhaps apologizing). By walking\running away it adds a 'trying to get over' element but he got caught.
Ollie is also a parent and knows something about correcting behaviors or lesson teaching. Basketball is not the important issue but having Jalen understand that as an adult there will be consequences for bad behavior. And he is an adult looking to have an extended NBA career.
One game suspension is reasonable and hopefully Jalen will have learned something by this. Hopefully it will be a valuable teaching moment especially if he's on the bench due to his own actions and unable to support the team on the floor.
By the way as an adult if he wants to race mopeds and jeopardize his basketball future he's free to do so.