Stock-market ‘fear gauge’ tumbles to nearly 4-year low. That makes some traders extremely nervous.

Wall Street’s favorite “fear gauge” has hit its most subdued level since before the pandemic after investors threw caution to the wind and bid up stocks at the fastest pace in years.

But rather than signaling that stocks are set to keep marching higher into the end of 2023, some analysts fear that the Cboe Volatility Index VIX, better known as the VIX, is sending an alarming message: Wall Street has become dangerously complacent in its assessment of looming threats, meaning any negative near-term shocks could send markets…