That goes both ways, doesn't it? In club football you can buy the players you like and create a team. In national football you play with who you have at disposal.
It doesn't go both ways, it goes exactly one way and that's having the best of the best players at a number of clubs and all of them in Europe ( 3 leagues each with a few teams + 1,2 extra from others like PSG and Juventus ), not spread into mediocre teams like some a few decades ago when there were restrictions such as max 3 foreigners, and you don't see a player like Messi going to play for Granada or AC Torino for obvious reasons, by the time he scored 5 and assisted 3, a big club offers big cash and gets him, like Dybala, neither was Ronaldo at 28 thinking of going to Sporting Portugal, if there ever is such an option, that's like at 34 or 35, but he will likely skip it.
Barca had 7 Spain players in the final but no Messi. Spain were dominant without Messi becuase it was enough, Barca wouldn't even make it past Arsenal in the Champions League that year which would look sad, but true if you think of it. While Argentina with Messi was destroyed by Germany.
Barca without Messi and/or injured Messi in the other match of the tie is a 0-7 against Bayern, a Spain can still beat Germany because they wouldn't have lined up Robbery, Javi Martinez or Alaba that played extraordinary then but a Barca without Messi against a Germany in that day would've made it easily past because Xavi was a nightmare destruction for them, but was completely invisible against Bayern, the same way we didn't need Ramos as RB because Alves was better and Casillas only had to save the team in the situations Valdes was great at ( 1 on 1 with the player ) or as Capdevilla wasn't even a player considered by Barca or Real cause of Abidal and Marcelo.
Same thing goes for Portugal getting destroyed by Muller & Co because Portugal sux even in the years penaldo si considered as ballon d'or, Ronaldo alone would hardly beat Albania or any team that decides to park the bus. Players hardly play in the EL and would loose 11-2 to Sevilla Substitutes or something like that. If it wasn't for Moutinho they wouldn't even have played at the WC and Sweden only has Ibra and a bunch of mid table-to-relegation fighting players in the top leagues and others in weak leagues.