Some of those are media bullshit probably.
But yes, he's lost some of that spark he had. It's normal though. Not all players can motivate themselves like crazy for 10+ years. Messi is more of a family man these days. Not his fault the club has no backbone and no plan.
What he does in La Liga is incredible. When he'll retire we'd have won almost 40% of our championships in Spain during Messi. I think 12 La Ligas is feasible for him.
The letdown overall is the Champions League. Could've won more, but you can't do it all.
Yes your right one man can't do it all because it's a team sport. Messi did his part last year in the champions league but was let down by his teammates