I read somewhere that truck drivers are an aging population. I think Covid has resulted in some finding themselves at home and just thinking life is too short for that kind of lifestyle.
They're an aging population, yes. The reason so many have vanished is they retired. Why? They were afraid of an economic slowdown brought on by the Covid lockdown would end up with them getting laid off and losing their retirement benefits. So they took the money and ran. Now some of the retirees are being lured back to work as independent contractors. That way they've locked in their retirement benefits and still get to earn wages.
