It's pretty easy to see what's going on. The dropoff from Okung to McQuistan is monumental when facing any kind of legit pass rusher. Bowie is a rookie, Sweezy isn't a rookie, but he's similar to one. JeanPierre isn't a rookie, but he's similar to one. IIRC, Carp has less than a full season of experience at guard.
Further, Pete is a coach who likes to force his opponents to do things. He puts Red Bryant at DE in the hopes that it will force his opponent to quit the run. He builds a line full of run blocking maulers in the hopes it will cause pass rushers to think twice before selling out, and it effects blitz calls too. But so far, that run blocking has been undermined by highly ineffective lead blocking, both by Coleman and others. Then you add in the injuries, and it's a minor miracle that Seattle's rush offense is still among the league's best. But it's still worse than it should be, and that's allowing teams to attack our passing game more than they previously could.
Green Bay has a very similar pass offense to Seattle. Poor pass protection, plenty of empty backfield stuff, lots of developing routes, lots of emphasis on YAC and chunk plays, and a wily QB who loves holding the football. The recipe has produced a ton of sacks and also a ton of offense. However, when Green Bay faced Seattle in 2012, they were sacked 8 times in the first half, and leading a drive was basically impossible the way they had that offense set up. So what do they do? They come out in the second half with an extreme dink and dunk offense. Every pass play unloads the ball in a couple seconds, usually for short yardage. It wasn't an awesome offensive display, but it was a big improvement. Green Bay dominated the second half of that game, mostly with defense, but with just enough offense.
What ticks me off isn't personnel, it's how Seattle refuses to adjust to a glaring problem. They are trying to drive down the highway at 60 mph with two flat tires. If they can't pull off the road and get things fixed, then they should at least adopt a different strategy. Stop forcing Wilson to hold the ball longer than his backup, inexperienced, piecemeal line can handle, start giving Wilson the green light to run more, especially when the receivers go deep vs. man coverage (we did see this vs. Texans, to Wilson's credit). Right now we have a pass protection situation that only Peyton Manning could make look good. Instead of attempting to emulate a Manning type game plan in the short term to compensate, Seattle continues to put their protection in unwinnable situations. That, plus the refusal to address the empty backfield / delayed blitz issue is maddening. Also, Derrick Coleman was a bad idea, but he's just a small part of the equation at this point.
Also, what do they know about Bailey that we don't? Has he stunk in practices since the preseason? Or is Seattle just in that much of a slump regarding the evaluation of talent on their own roster (Person, Lotulelei, Howard, Bradford, Mike Rob, Coleman, etc)?