I would argue that bus drivers have a much larger impact in terms of lives lost if things go wrong, yet they have significantly lower wages and require less training. The same goes for pilots and air traffic controllers.

You can argue that but what’s your point? The current truck driver training system works well enough AFAIK. Do you demand more training?

How is it decided how many regulations are "enough" for a given field? It seems they are on an ever-increasing ratchet mechanism, often driven by mass hysteria.