In one of last decade’s best opening sequences, filmmaker Carlos López Estrada captured the beating heart and aching soul of the city of Oakland. “Blindspotting,” his 2018 directorial debut, put Estrada and that East Bay city strategically onto the pop culture map. Now, the 32-year-old Mexico City native turns his focus to a region he knows much better — his home, Los Angeles. Whereas the terrific “Blindspotting” concentrated on raising the voices of two characters (portrayed by East Bay best buds and co-screenwriters Rafael Casal and Daveed Diggs), Estrada this time tackles something more challenging, stitching cohesively together 27 perspectives from Los Angeles young-adult poets.