Every year, Fortune publishes the Future 50, a ranking of the world’s largest public companies by their long-term growth prospects, co-developed with Boston Consulting Group (read more on the Future 50 and our methodology). In this series, we assess trends related to the future growth potential of businesses.

A small fraction of all companies is responsible for the majority of wealth creation in the stock market over the long term: A recent study of 28,000 U.S. firms shows that almost all net shareholder value created between 1926 and 2022 was attributable to only 2% of the sample.

Leading the pack in terms of total value generated—over the entirety of the nearly 100 years studied—are digital technology players, specifically, the “MAMAA” companies (Meta, Amazon, Microsoft, Apple, and Alphabet), which now constitute more than a quarter of the value of the entire S&P 500. All five are currently among the 10 most valuable firms worldwide—with Nvidia and Tesla rounding out the stable of tech giants among the top 10. Across the Pacific in China, players like Tencent, Alibaba, and privately held ByteDance lead the valuation rankings.

Stumbling blocks for the tech sector

Recently, however, the growth promise of the technology sector has seemed less certain. In China, the government launched a crackdown on its tech champions and their superstar CEOs, enhancing data privacy measures and increasing its antitrust vigilance. Now, the CCP is putting pressure on digital entertainment players by severely restricting internet usage for minors. In the U.S., increased public scrutiny over the impact of social media (which is alleged to cause depression and contribute to social polarization) is putting pressure on players like Meta, while Amazon finds itself facing a landmark monopoly case.

Rising geopolitical tensions are also affecting tech players—from the Biden administration doubling down on export controls of advanced chip manufacturing equipment to China, to the much-discussed TikTok ban, or the recent calls to halt a partnership between Ford Motor Co. and Chinese battery manufacturer CATL.

Finally, there are the layoffs, now totaling over 400,000 workers through 2022 and 2023 (or roughly 4% to 5% of the total US tech sector workforce). While these are partially correcting for pandemic-era over-hiring, they also reflect a shift in investor focus from long-term promises to short-term payoffs, in reaction to increased interest rates that make riskier long-term investments less attractive. Higher rates have also contributed to the current venture capital “winter,” in which deal counts and values have fallen to 2020 levels and startup exits as well as capital raised are at long-time lows.

Given these significant headwinds, it is no wonder that Fortune’s ranking of the 100 Fastest-Growing Companies is no longer dominated by the tech industry. The top 10 are now firmly rooted in the physical realm, selling building materials or wires, refining steel, manufacturing cars, or drilling for oil. Only 17% of the included players are from the tech industry—roughly the same representation as, say, the energy sector—while the MAMAA companies are nowhere to be found.

Does this indicate that tech is no longer the growth engine of the economy? Or, as Fortune CEO Alan Murray suggested, will the trend towards dematerialization and digital technologies continue?