They suck as a unit doesn't mean they suck individually. For the most part their all low usage guys who can play defense and move the ball, occasionally hitting the open three. When they're all playing together there being asked to create for themselves leading to more contested shots and running into traffic, which in turn is affecting their defense as they're over helping. Oni and Morgan have already proven to be much more effective NBA players when a part of the regular rotation, same applies to Niang who with a more collapsed defense struggled to get his shot off cleanly.
Shaq Harrison btw is absolutely clueless when it comes to running an offense. Probably not much of a surprise that they looked better in preseason when NWG was running the third unit combined with Hughes who is the only player amongst the scrubs capable of creating for himself.