"American", "European"? Free / Open Source software like that does not have nationality, it's a collaborative effort of thousands of developers around the globe. It's irrelevant what nationality the initial founders once had.
>It's irrelevant what nationality the initial founders once had.
That is not the point.
Most big open source projects end up with an entire commercial ecosystem backing them. KDE has probably directly created many more jobs in Europe/Germany than GNOME. Such things should be taken into consideration when determining who deserves grants paid by EU/German tax payers.
GNOME Foundation is based in Orinda, California, United States
KDE e.V. is based in Berlin, Germany
Both have corporate and individiaul contributors from around the wold but these are not indentically distributed with Gnome being more popular in the US compared to the EU. Calling these two desktop environments "American" and "European" is of course not painting the full picture but it isn't entirely wrong either.