A winning football team needs several things- talent, coaching..... and heart. Heart is a nebulous factor- it involves leadership, but it also requires individuals who refuse to fail in crunch time. The Vikings lack all three- talent, coaching, and heart.
In the off-season- after an historically bad draft the prior year with only one draftee (from the 4th round) even seeing the field and then proving to have zero ball skills- the goal was to improve the running game. With lesser talent and the same toally inoffensive offensive line. The coaching is unable to find ways to score from in close and pick up short yardage plays by any means- run, pass, trickery. The defense can either slow the passing game or slow the running game, but never really stop, and never both. The pass rush consists of one person accompanied by "Chinese Fire Drills" that never sniff the QB (see Kassulke, Karl, and Stram, Hank for explanation).
But the critical problem is lack of heart. It appears that Adam Thielen and Dalvin Cook were leaders whose contributions to scoring outweighed their statistics, and Zadarius Smith and Eric Kendricks were leaders whose presence in motivating teammates was more important than their own skills and stats (though Smith did rush the passer approximately 400% more effectively than his successors, especially the $13 Million Man).
A team that only needs to make one play week after week to win, and consistently fails week after week, is a team that needs heart. You can't grow that from within- some leaders just make it happen because that is who they are. I don't see that here, this year.
Those who wanted the team to be dismantled and rebuilt six months ago will have their wish starting in 15 weeks. But entering this off-season with the same scouting staff that recommended the current roster is not particularly reassuring.