The name Julien was really popular in France during the 80's and 90's, so much so that it became the 26th most common name for baby boys in the 20th century despite the fact that it was quite rare until the 80's. It is still a top 100 name, but I personally find it a little dated. It's kind of like Jason in a sense. Not bad names, just overused at a certain point in time.
https://pcd.wikipedia.org/w/index.php?search=Julien&title=Sp%C3%A9cial:Recherche&profile=advanced&fulltext=1&ns0=1