Nasdaq 100 ETF falls 0.7% after hours; SPDR S&P 500 ETF down 0.4%

The Fed's explicit link between AI-driven valuations and financial-stability risk gives after-hours ETF weakness a narrative beyond routine drift, even though the moves themselves are modest. The simultaneous FAA ground stop adds an unrelated operational shock, so the read-through is less about tech fundamentals than about how markets price multiple, overlapping uncertainties. Whether the valuation warning alone sustains pressure once regular trading opens is the open question.