The market's decline due to the interest rate cut is very easily explained by this table that was also prepared by the Fed for the meeting.
If the data on economic growth and unemployment is fine, then clearly not everything is fine with inflation. It has been increased to 2.5% in 2025... But the main reason that triggered the sell-off is the chart showing the rate cut. Now the interest rate forecast for 2025 has been increased by 0.5%... which means the Fed plans to keep the rate sufficiently high for a long time, which immediately reflected in the sell-offs.