Jim Cramer is done with fossil fuel stocks. It’s not that the fundamentals are bad, the irascible investment guru and Mad Money host told CNBC anchor Becky Quick last week. The dividends are great. But “nobody cares,” he explains. “The world has changed. There’s new managers [trying to] appease younger people who believe that you can’t ever make a fossil fuel company sustainable. In the end they make fossil fuels. We’re in the death knell phase.”

Quick rushed to clarify. “The death knell phase for the stocks, but not the death knell phase for us using fossil fuels, right?” Cramer didn’t offer much comfort, comparing multinational oil and gas companies—historically, some of the world’s most profitable—to the comparatively meager and maligned tobacco industry. “You can tell that the world’s turned on them.”

Cramer has been wrong before—most infamously in emphatically advising investors to buy Bear Stearns days before it went belly up in 2008. Still, it’s rare to see such dire projections about the health of the world’s biggest polluters come from outside the ranks of climate campaigners, much less from CNBC talking heads. Yet the array of threats facing the fossil fuel industry in 2020 could make for other strange bedfellows. “What Jim Cramer’s talking about is definitely a sign of the times. This is a topic that has gone a long way up people’s radar in terms of priorities, but in particular these last three years,” said Andrew Grant, head of Oil, Gas and Mining at the British think tank Carbon Tracker.

Overall, oil and gas producers have lost $400 billion in market value over the last four years. ExxonMobil, the world’s most valuable public company in 2012, saw its stocks drop to nine-year lows this week, and Goldman Sachs recommended that investors cash out. It’s hard to pinpoint any one factor as the source of the oil and gas industry’s stock troubles, Grant said. Public perception looms large. Big polluters face ever-louder criticism from activist outfits like the Sunrise Movement and Global Climate Strikes, as well as a string of climate-related lawsuits and activist investors who—controlling some $35 trillion worth of assets—are demanding emissions cuts, as activists on college campuses and within pension funds call for outright divestment from producers. “Fossil fuels have a P.R. issue,” Ben Cook, a portfolio manager at BP Capital Fund Advisors, told CNN. “As long as the market perceives them to be the culprit for carbon emissions, they will have a difficult time.”

Activists’ complaints are well founded. For decades, popular wisdom suggested that the world would at some point run out of oil. What’s clear now is that there’s far more of it than we can safely afford to burn. Recent estimates suggest oil and gas companies would have to forgo almost $900 billion—one-third of the sector’s current value, representing 84 percent of reserves—if the world’s governments moved aggressively to cap global warming at 1.5 degrees Celsius (2.7 degrees Fahrenheit); meeting a two-degree target would still mean writing off nearly 60 percent of reserves. Across the board, meanwhile, traditional energy executives have been loath to invest more than token amounts in carbon-free energy, preferring to spend big on new unconventional drilling and exploration. Exxon has been more bullish than most on this front, with BP and Shell taking a slightly more conservative approach.