S&P 500 set-it-and-forget-it strategy due for a rethink: experts

The S&P 500 index closed at a new all-time high on Wednesday amid a federal government shutdown. It rose to a new intraday high early Thursday.

Prior to that, the index — which is focused on large-cap U.S. equities — had risen almost 90% since the equity bull market began three years ago, thanks in large part to new AI developments, Morgan Stanley Wealth Management noted in Sept. 29 research.

Nevertheless, experts say it may be time to reconsider the set-it-and-forget-it S&P 500-focused strategy, famously touted by legendary investor Warren Buffett.

"The S&P 500 is broken," said Michael DeMassa, who is a certified financial planner and chartered financial analyst, and the founder of Forza Wealth Management in Sarasota, Florida.

Many investors assume investing in the S&P