Is the stock market in only the early stages of a dramatic transition from growth to value?

The current century is only two decades old, but already it’s been an extraordinary one. For investors, it’s been characterized by four bear markets and a series of asset bubbles, according to John Linehan, portfolio manager of large-cap equity income and U.S. value strategies at T. Rowe Price.

Most major markets are in bear territory largely because of “multiple compression,” Linehan said at press event in New York City last week. On average, multiples around the world are down 21%.

The reason for the decline “hasn’t been earnings,” Linehan said. “Today, multiples are below their 20-year averages.”

For two decades, inflation was barely on investors’ radar screens. “Now it seems like inflation matters and it’s the only thing that matters,” he said.

Bear markets, Linehan noted, are a lot like Leo Tolstoy’s “unhappy” families. “No two are alike,” he said, referencing the famous introduction to the Russian novelist’s classic Anna Karenina.

Linehan questioned much of the conventional wisdom surrounding today’s stock market, arguing in a presentation that “accepted market truths may not work this time.” Fundamentals have improved for value relative to growth, prompting him to question whether growth leadership will resume, despite many investors’ infatuation with the tech sector.

Investors also are trained to believe that banks will “underperform in a recession.” However, today’s banks have much higher lending standards and have far more capital strength.

Conventional wisdom also holds that consumer staples stocks are the place to be, and many have outperformed this year. But Linehan observed that pricing power is “unevenly distributed,” and some consumer staples companies are confronted with intense input cost inflation.

Another popular belief is that European equities should be avoided. That ignores a compelling reality, in Linehan’s view. Many European companies simply are far more competitive than many investors believe.

Finally, Linehan questioned whether last decade’s disruptors might become the current decade’s disrupted, as tech companies enter each other’s primary markets to take share. In a conversation after the presentation, Linehan expanded on what this means for some stock market darlings.

When the financial crisis began 15 years ago, digital advertising was dominated by Google, now Alphabet., But online advertising accounted for only a fraction of all advertising and Alphabet was able to enjoy secular growth.

Today, digital advertising is 65% of all advertising, which historically has been a cyclical business. To some extent, this makes Alphabet a victim of its own success, as cyclical companies typically command lower price-earnings multiples than those with steadier revenue streams.

Similarly, Facebook was a huge beneficiary of the “network effect.” But just as networks can grow in an exponential fashion, when that growth slows and usage begins to decline, the falloff in online interactions can be equally powerful.

“We’ve almost seen leadership flip on its head,” Linehan said. “Still, robust expectations [have been] placed on growth relative to value. We think growth expectations may disappoint.”

Balance the risks against potential rewards, and at the very least, it suggests that caution will be warranted.