https://www.fool.com/investing/2020/08/25/dow-jones-sinks-after-big-changes-announced-apple/
It’s important because it will reduce the weighting toward the energy industry , but it’s more important not to use this as an indication of how markets are doing.
$SPY S&P 500, $QQQ NASDAQ 100, $IWM Russell 2000 have more stocks from a broader spectrum and are usually regarded as more realistic benchmarks for markets . The 30 DOW stocks continues to change and IMHO is more marketing and keeping the index inflated, then a reflection on economic activity .