These measure exist to ensure cultural and creative industries, European content doesn't mean content recorded in Europe by Americans...it's content from people in the country of origin. And all creative industries (cinema, music, etc.) don't only give money to few "millionaires", there is a lot of "common people" working in recording studios, live events, movie making etc.Incredibly nativist for countries demanding their people accept high levels of immigration from very different cultures.
But why not? They can decide having too much Hollywood is against their peoples preferences but I bet most people wouldn't vote for that. Most people probably don't care but this is a buy off for rich actors and directors. Just like the industry that makes so many millionaires gets tax breaks in America for filming a movie there. Politicians love giving freebies to famous millionaires in the name of the common man.