“The company boards seem to think they need to keep executives from fleeing a sinking ship,” said Sarah Anderson, an executive compensation expert at the Institute for Policy Studies, a Washington research group. “But when you protect people at the top from risk,” she said, “you’re not incentivizing them to shift to another approach, like making a transition toward more renewables.”

The lopsided pay structure in coal is a reflection of an economy marked by widening income inequality, where gains at the top of the income scale have come amid stagnation, or losses, at the bottom. But with coal mining, the yawning gap takes on an added significance. President Trump has made lifting the fortunes of blue-collar and rural Americans a centerpiece of his administration.

When Mr. Trump signed an executive order in late March to roll back Obama-era climate change efforts, which would have spurred a shift from coal to renewable forms of energy, he was flanked by coal miners who applauded the move.

Though employment in coal mining has been growing since the fall after a long period of decline, the numbers have been minuscule — a net increase of 100 jobs in the latest jobs report for March. Since September, overall employment has increased by 1,700 to just over 50,000 workers, according to the Bureau of Labor Statistics.