that is not true. In Europe, when you say "I have 30 days of holidays", that means 30 days that you can personally take off whenever you want (more or less). National holidays, like Christmas, are never counted because they are free for everybody. So assuming the US and Europe have a similar number of national holidays, you get about 2x more personal holidays in Europe.

(Again, this varies. In Germany it is usually around 28-30, in Spain around 22)