I agree with McDermott to a point. He didn't say "Culture is everything." He's basically saying if you don't have players that go about things the right way, your strategy won't succeed...likely long term. Look at Miami. Gase took a page from McDermott's book and cut talented players that don't fit what they're trying to do. As someone said, they put themselves ahead of the team (Landry, Suh). Miami looks better for it this year.
Having said that though, there are obviously flaws in the talent area and the coaching area. The TEAM is young...not individual players. The TEAM has only been together 2 years. We loved this team last year because this TEAM, despite the lack of talent, won enough games to make the playoffs...over the previously more talented teams that didn't have the right culture. They have added new pieces, that individually have to grow and learn...and collectively have to grow and learn.
We're frustrated now because the team hasn't played well...particularly the offense, which has the most new starters. I'm going week to week this season. If they bounce back this week and play better football, we'll all feel better. I want to see steady improvement...from the rookies, the coaches and the team. It doesn't mean I've drunk the cool-aid. It just means that I'm willing to be objective and patient. (For now.)