“Bond investors are receiving almost nothing for their money, and the situation is getting worse and worse,” he said. “But they’ve gotten used to it. They don’t realize how bad it is. And before they know it, well, they’ll be cooked.”

His utterances in those days often moved markets, and his early-morning yoga ritual at Newport Beach, Calif., was widely chronicled.

Early in his tenure at Pimco, Mr. Gross was known as a skillful bond trader who pioneered the use of mathematical models to eke out steady profits. He also gained fame as an analyst of broad economic trends, which he used to inform the firm’s investment strategy.

He had a homespun style that he used in books aimed at a popular audience, like “Everything You’ve Heard About Investing Is Wrong!: How to Profit in the Coming Post-Bull Markets.” In that 1997 book, he said the solid returns produced by bonds would shield investors from the disappointments of the busts that inevitably followed boom markets in stocks.

But Mr. Gross has not been a dominant figure in finance since he was forced out of Pimco amid accusations that he had mismanaged the firm, where he was a co-chief investment officer. Mr. Gross and Pimco settled a lawsuit over the dispute in 2017.