Is the law of gravity at play in football or is it simple negligence?

Last week, Argentina finally qualified for the 2018 World Cup in Russia and it was great. A hat-trick from arguably the World’s best footballer, Lionel Messi against Ecuador coupled with a 3-0 loss by Chile to Brazil guaranteed this. All that would be talked about may be the heroics of Messi, the relief that Argentina and their star player would be at the World Cup or even the argument about the Balon D’or but the struggles through the qualifiers must not go unnoticed.
For three years, Argentina had been one of the in-form footballing nations, reaching the final of the 2014 World Cup, Copa America and Centenary Copa America. Despite the fact that they did not win any trophies, struggling during the qualifiers came as a mystery to a lot of people. It was both the drastic change in results as well as the quality of players on the pitch that was baffling. However, it confirms a pattern in world football with several teams dipping in form after years of dominance.
The Netherlands played at the final of the 2010 World Cup with their golden generation that included players like Wesley Sneijder, Robin van Persie, and Arjen Robben, losing to Spain only by a lone goal in extra time. Then at the 2012 European Championships, they crashed out at the group stages without registering a single point and could not even qualify for the 2018 World Cup. Spain won the 2008 and 2012 Euros, and the 2010 World Cup and were then unceremoniously dumped out of the 2014 World Cup. Even current World Champions, Germany, had a horrible outing at Euro 2016. Whilst the argument of ageing squads cannot be discarded, the transition for teams from one generation to another should not always mean a slump.
Argentina and Brazil have always churned out fantastic players and not forgetting Europe with the quality in Spain, Italy and Germany, but the handing of the baton is like the USA in the 4x100M relay at the 2008 Olympics, someone just drops it. It seems to be that the previous generation stay on too long, the younger generation come in too green and nobody is willing to try anything new such as dropping a trusted player, albeit old, for a younger player however inexperienced. After all, if it ain’t broke why fix it? The only problem with that theory in football is that it tends to break on the biggest stage with a lot at stake.
In the end, it is only natural for players to decline in performance with age but is the cost to the teams also a natural occurrence or lack of vision by Football Associations? They could have looked to their Leagues, developed youth football or played more friendlies with development as opposed to FIFA ranking points in mind.
Perhaps this is another case of or may be it is a case of what goes up must come down, or simply nature versus nurture.