Attitude.
It's infectious.
There's a huge difference for OL when they are allowed to attack vs being on the receiving end of impacts. Especially for a QB who can't stay in or step up in the pocket where the geometry gets so heinous, which makes the pass blocking twice as hard. Even from a pure mentality perspective, it's passive vs aggressive. On top of that, we have two gaurds who are as aggressive as it gets if allowed to be.
Play action derived from the above allows Russ games that are as easy as it gets. That lob pass to Dickson was a perfect illustration of it. They were so concerned about the run game that no one even covered him. Russ can get deeper pass drops due to PA because the defense actually has to take a second to read run vs just setting out to get the QB from jump. We're rolling him out again to give him space to see downfield and put him in a position to improvise. Russ' movement is now much more controlled instead of chicken with the head cut off. He's now able to put up historically efficient games again because, not only does he not have to do it himself, his job is now as easy as it gets for a QB.
The defense WAS hung out to dry by one of the most horribly inconsistent offenses. 3 n outs constantly, not throwing on time, not throwing at all, HUGE losses for sacks due to lack of pocket presence and retreating 15 yards for 2nd and 25 or 3rd and 25, etc. Now the drives are controlled and sustained, we might get a 3rd and 7 or 8 every now and then, but we're now working mostly with 3rd and short and our 3rd downs are being completed at a really high percentage. This makes it so the defense doesn't have to be on the field all game after one sorry 3 n out after another. The defense now has an actual ally in the offense instead of a faction that might give you 3 to 5 big plays here and there and a handful of field goals and maybe a TD if you're lucky.