The reduction in price target from $23 to $20 by a reputable analyst firm like Keefe, Bruyette & Woods could lead to a negative short-term sentiment among investors, potentially causing a decrease in the stock price of Financial Institutions (FISI). The maintenance of a Market Perform rating indicates that the analyst does not see significant upside or downside from the current levels, but the lowered price target suggests a recalibration of expected performance, which could be interpreted negatively by the market.