Josh Richardson has high basketball IQ
Having spent time with multiple NBA organizations, Richardson has been able to pick up experience and knowledge from great players and coaches all over the league in his nearly seven seasons as a pro. Namely, his time in Miami where he was mentored by Dwyane Wade and learned under one of the most respected coaches in basketball, Erik Spoelstra. He understands what's happening on the floor and frequently showcases his high IQ with his play.
Take a look at this play. Richardson is matched up with Duncan Robinson and sees the screen from Bam Adebayo coming. Knowing that the offense could be trying to fool him, he stays put in case the screen is a fake and his man chooses to roll to the basket. As soon as he sees Robinson cutting to receive the ball from Lowry, Richardson fights over the screen in time to get a hand up and contest the shot, forcing a miss.
A less sharp player might get stuck behind the screen or get caught not thinking by the defense. This was a pretty routine play, but it's sequences like that where he shows solid defensive fundamentals and reminds me a bit of watching Dejounte Murray.
Richardson's high IQ and instincts are evident in nearly all aspects of his game. On offense, he's consistently playing his role correctly. On defense, he's very light on his feet and stays active. J-Rich is never afraid to stick out his hand and swipe the ball away from an unsuspecting offensive player, and he knows how to play passing lanes and when to come over for help. He's currently tied with Devin Vassell for second on the team in steals per game at 1.1.