Gia Coppola had a famous filmmaking surname, a promising debut film under her belt and a timely idea about skewering internet influencer culture, but it still took nearly seven years to get “Mainstream” off the ground. Her film, an internet age update of Elia Kazan’s 1957 satire “A Face in the Crowd,” stars Andrew Garfield as a street corner philosopher who a young artist played by Maya Hawke starts filming. Garfield came on not just as a star but as a producer as well which helped a great deal. “Mainstream,” an IFC Films release, is available in theaters and on demand Friday.
