Alarmism over climate is of great benefit to many, providing government funding for academic research and a reason for government bureaucracies to grow. Alarmism also offers an excuse for governments to raise taxes, taxpayer-funded subsidies for businesses that understand how to work the political system, and a lure for big donations to charitable foundations promising to save the planet. Lysenko and his team lived very well, and they fiercely defended their dogma and the privileges it brought them.
But if governments could only act when there was unanimity, no law on anything would ever be passed. The US invaded Iraq, bailed out banks and passed universal healthcare with much less consensus than exists over climate change. In short, the sceptics are not the block to action.