I hope Tyler chimes in on this.
To begin, I am not going to claim that I understand his defense fully.
Jay's defense is a swarming defense, base on weak side help. This defense causes turnovers and baskets in transition. Sometimes, this defense looks terrible. This happens when they over commit leading to open 3's, or they over commit and watch the opponent make an uncontested lay up.
Usually, there are players in the lane to alter layups and some pressure on 3's. A low percentage of the time, it leads to open lay ups the other way, which is a huge benefit.
Additional "BIGS" will not improve upon this. Players like Josh Hart will improve upon this. Lanky guards who pressure the ball and can rotate on opponents passes is key.
Chef does not stay at home, he effects plays will sitting at the top of the key.
It's a winning formula that requires long guards and athletic players.