I never really buy into the "we beat ourselves" type conversations. To me that's a comment any team that ever loses can say at any time.
I mean Kyle is good for a head scratching call every game as well, but doesn't get called out that much because so much of what he calls works.
To be clear tho....NOBODY has been able to run on the 49ers this year. They only give up 77.7 yards per game. Yes...they can be beat deep...but the gameplan you are describing is pretty much the gameplan of every single one of the 10 teams the 49ers just beat on this win streak. "Protect and run the ball effectively" has resulted in a combined 305-144 score (30-14 ea) over those last 10 games.
I am sure you are correct though in that Seattle will play inspired. They'll have the "paying with house money" attitude and they'll play hard.
As for adversity, I'll respectfully disagree. First off, they were down 10 to the Raiders and won the game. He'd have had a game winning drive if Gould didn't miss the FG at end of regulation.
Also...I think people forget this. For as well as Purdy has played, the 49ers are kinda playing with house money here as well. They were just crushed by injury early in the season and Purdy is their THIRD QB. I mean did anyone think they'd be in this spot when Jimmy broke his foot?
For myself, I'm just enjoying the ride. If they lose, it'll suck. Particularly if they lose to Seattle and I have to hear it from you guys all offseason.

As much as it'll suck tho, I never saw the 49ers this year as a real contender for the SB.
First, I expected them to lose some games while Trey took some lumps. Then, we were right back to Jimmy and then the D got eviscerated by injury and then they got crushed by KC. I always viewed that as more of an anomaly, but at that point they were 3-4 and teetering on a lost season.
The fact that they ripped off a 10 game win streak and are the 2 seed in the NFC is all gravy for me.