Well, that's conflating issues. Our SG's were poor. They've been poor more often than not.
They are not however responsible for running the offense and getting the right guys the right looks at the right times, nor are they the guarding the point of attack frequently on defense and responsible for the initial breakdown many times, leaving everyone else scrambling. IT is killing us with how easily he gets rubbed off and left behind on screens as well as he's pretty much non-existent on rotations and help defense due to his size.
Some focus too much on who actually hits the shot against us. Have to look at what led to it and the body of work on any given possession. It's an issue for us that opposing PG's can get where they want, or make the passes to whom they want without the passing lanes or their vision to the target cut off/down. That has a direct effect on the tempo of the game. Little resistance from our end at the point of attack lets the opponent get into the rhythm they want and get the shots they want. Of course our poor rotations play a part and everyone has a responsibility there, but we're at a disadvantage just about every night when our PG is giving little resistance. That doesn't always show up in the box score though. It's where the picks are set(get into the ballhandler and the picks are set farther from the basket or are tougher to use as you push away from the spots the opponent wants), how freely you can come off them, how much passing lanes are effected, vision of the court and offense, taking a few dribbles left or right unobstructed to deliver a better pass in rhythm, targeting IT in P&R's or help actions as they know he's a liability on rotations/help defense, etc.. This all has an effect on the flow, the rhythm. How many points MCM had is only one aspect of the defense tonight.
In football it's not good if your CB's and SF's are below average and getting lost in coverage. It's a problem. However, if your defensive line is awful, doesn't put pressure on the QB and can't stop the run game to save their lives, that's a bigger issue than the CB's. The CB's would always be at a disadvantage if your defensive line isn't applying pressure and not stopping the run, it sets things in motion. It effects the rhythm of the opponent. It's part of the foundation of a good defense, having a solid D-Line. Without it, breakdowns happen and everyone scrambles. It's similar to this situation. If you repeatedly can't stop or effect the point of attack or rhythm of the attack, everyone will be at a disadvantage. Others deserve blame, but it also distracts from the main issue or one of the main issues.