Since 1968, Neil Young—who was born in Toronto in 1945—has been making raucous, astringent guitar music, both as a solo artist and with his longtime backing band, Crazy Horse. On occasion, he has veered toward tenderhearted folk rock, as a member of Crosby, Stills, Nash & Young, and on records such as “Harvest,” his fourth LP and the best-selling album of 1972. Young has spent most of the past fifty years arguing for environmental causes, even (or especially) when nobody was keen to listen.