JPMorgan shifted gears on air mobility stocks Archer Aviation Inc ACHR and Joby Aviation Inc JOBY, downgrading them despite strong sector enthusiasm.Analyst Bill Peterson adjusted Archer Aviation stock to a Neutral rating and Joby Aviation stock to Underweight, noting their significant market gains surged past what fundamentals justify.Market Enthusiasm Outpaces FundamentalsPeterson highlighted that Archer and Joby have outperformed the Clean Tech sector, gaining 145% and 86%, respectively, over the past si ...