The Cowboys did invest in linebackers in Jaylon Smith and Leighton Vander Esch. Then they spent another 1st round pick on Micah Parsons. In theory, the Cowboys should have Parsons and Vander Esch, two 1st round picks at linebacker. But Dan Quinn moved Micah to DE, and Vander Esch has chronic health issues. They spent a 3rd round pick on Overshown, only to have him go down in the preseason to a freak knee injury.
It is easy to criticize, but it's not like the Cowboys haven't tried to upgrade the linebacker position. The reality is that a lot of teams try to get better at key positions, and for whatever reason, the efforts fail. This is why Kansas City spent 5 decades between Super Bowls, and why Matt Millen spent three 1st round pick at wide receiver for the Lions before finally snagging Megtron. Matt Stafford was a #1 overall pick, that for whatever reason couldn't win in Detroit - no matter how many times the lions drafted Olinemen, running backs and wide receivers to help him.
It takes a little bit of luck, and health to become winners. Does anyone really believe the Eagles would have been in the Super Bowl a year ago, if not for the 49ers bad luck at getting a QB. Heck, they traded for Garoppolo, spent a draft fortune to move up for Trey Lance, and then simply lucked out by using the last pick in the draft on some unknown kid from Iowa named Purdy. Then Purdy got hurt in the Championship game, opening the way for the Eagles a year ago.
I know everyone is frustrated by 28 years of futility. It sucks. I also realize that no one gets graded on a curve for trying really, really hard, and then continuing to fail. But honestly, Cowboys fans were blessed and spoiled by going to 16 Championship games and 8 Super Bowls in the first 30 years of Super Bowls between 1966 and 1995. The worm turned, and now we fans and the team are getting a taste of what so many other fan bases have put up with for years. Again, it sucks. But sometimes, a little gratitude for what you've had in the past, instead of bitterness over current problems helps with your frame of mind.
I'm grateful for all the years of winning in the past. And I sympathize with younger fans who didn't get to experience the joy of being perennial winners. But life and the NFL doesn't owe the Cowboys fans success. That's just a cold hard fact. I believe the players, coaches, front office and owners want to win as much as any team in the NFL. What happens now is they keep trying - like 31 teams do every year, when they come up short.
That isn't "accepting" losing. It is simply the willingness to keep trying, even in the face of defeat. That's sports, folks.