Automakers and dealers are worried about affordability as supply-chain woes keep inventory levels low and customers are hit with increased inflation, high gas prices and climbing interest rates. Domestic and foreign automakers on Friday posted U.S. sales declines for the first three months of the year, with Cox Automotive Inc. forecasting the period could tally the worst first-quarter volumes in a decade. After more than a year of a global microchip shortage bit hard into inventory levels, the slide is leaving dealers empty-handed and demanding customers pay the sticker price or above. The pri…