Always nice to get different insight
Messi has struggled a bit early on to be as effective for Argentina as for barça, but not more and it's been years. 2011 I think is the turning point, although messi had an excellent 2010 world cup playing as a sort of trequartista. In 2014 he was the crucial contributor to like 75% of Argentina's goals. But Argentina sucked, especially Higuain, Di maria save for his goal, etc.
That said you'll agree I think that messi isn't just the best club player ever, he'sthe most individually gifted
No one could ever dribble with such ease and frequency through 2-5 players. And dribbling in itself is the pinnacle of football skills. The other part of genius is vision. And here, although not as clear cut as dribbling, Messi is also a GOAT pretender. Finishing ? He's easily top 5 in terms of goalscoring, and only one of the others (Bikan, Muller, Pelé, Romario ? of course a few other names could be mentioned here) has a realistic claim to best ever. Playing in the very beginning of football's professionalization.
Messi is the greatest ever.
You may have a point about Platini, Baggio, Zidane > Zico, I'm way too young to judge, only watched Zidane (a lot). Here in France Zidane is universally rated as the best french player, both in skills and careers, never mind Platini's ballons d'or
that said messi is the most individually gifted player there's ever been, NT or club doesn't make a difference in this regard.