(Bloomberg) -- As an ESG fund class facing mass downgrades attracts vast client flows, industry insiders confess they don’t understand why investors aren’t being more cautious.Most Read from BloombergChief Justice Temporarily Stops Release of Trump Tax ReturnsLottery Winner Keeps $30 Million Jackpot Secret From Wife and ChildEven More Dry Shampoos Found to Have Cancer-Causing AgentNorth Korea Fires 17 Missiles in Biggest-Ever Daily BarrageChina Markets Rally After Unconfirmed Social Posts on Reo