As Leo Messi and Khaled said, historically, Italian, German and English players always stayed in their country.
In 90s, almost all top:
Spanish players played in La Liga.
All best Italian players played in Seria A.
All best English players played in EPL.
All German players played... more or less in Bayern, as always.
Then we have other countries like Brasil and Argentina, where all players go to Europe as fast as possible.
And even there we have some weird connections.
In 90s and 00s, while Milan was in top2-3 clubs in the world, they always had a connection with Brasil and Brasilian players.
While Inter for example, was always more oriented towards Argentine players.
Netherlands was always selling their young prospects.
In 90s to Milan and Barca.
Later even to EPL.
Portugual and their league was always a place where teams were buying young South American players who are not good yet for Barca or Real, so Porto/Benfica were a next step in their development.
France was always a league with lots of talents and in 90s, their players usually played in EPL, Italy and Spain.
Lately, since Italy is semi dead, their players go to Barca/Real/AM, EPL or Bayern/Dortmund.
There are other historical and weird connections.
For example, Croatian players since 90s, were always fitting the most easily into German league, into their culture, climate and a style of play.
Croatian players had some success in 90s in Italy. And some success in Spain over years.
On the other hand, like 95% of Croatian players turn into a total disaster in EPL, and England is the worst place for all Croatian players. A totally different mentality and a style of play.
Regarding Barca, Barca always had the strongest connection with Brasilian players since Brasil played "joga bonita" plus Catalonia has a warm weather and a culture similar to Brasil.
So, for Ronaldinho, Rivaldo, Romario, R9, Neymar and co, it is way more likely that they will fit more easily into Barca's Joga Bonita playful football than into a cold German culture, mentality and weather.
On the other hand, German league is a good place for players from Poland, Czech Republic, Croatia, Turkey and similar.
In Germany there are millions of people from Croatia, Turkey and similar and people see Germany as their home, to some extent.
On the other hand: Turkish players at Barca... it never works.
As I have said, in the past Italians were never leaving Seria A.
It only started when Juve was relegated and we bought Zambrotta.
Then Seria A bankrupted and some of their players started to move to Psg and to other richer European clubs.
Regarding Germany, German players have some weird connection with Germany and they very rarely leave their clubs.
Even if they somehow leave Germany, in majority of cases those are players NOT from Bayern. Like Ozil, Khedira.
Or they move aged 30, like Ballack.
Kroos is one of rare examples of Bayern's German players leaving in their prime.
Some will reply: each player is unique.
True.
But then, Barca has good connection and good experience since Cruijff with Dutch players.
And we have horrible experience with let's say Turkish or Russian players.
Some things just naturally click better.
So, regarding ideas that we should buy Goretzka, Havertz etc, that will happen only in Football Manager.
** Oh, and the same is with English players, they almost never leave their clubs. Except Beckham in the old age...
In reality, players whom Barca will always buy are:
1. Brasilian players
2. top Argentine or other South American players
3. Dutch players
4. French players
5. Catalonian and Spanish players
6. and a random dude here and there like Rakitic, Zlatan etc
So, imo, guys, you shouldn't lose too much time about dreaming of German/English players.
