Interesting post and question that has to be answered in several parts.
Safety is paramount to all airlines, the industry's record speaaks for itself and it is wholly wrong to doubt this fact. Certainly in the UK we have the heaviest regulation and best systems in place to prevent circumvention of the rules and quite right too! Not sure if you can compare the safety of road haulage/airline because of the vast differences in parameters but air travel is without doubt and remains one the safest forms of transport there is.
Economically, the problem with running an airline (I have sat on the Board of two or three) is that the numbers are so big. I do not know what it costs to lease a Scania tractor unit but I can tell you a Boeing 767 will cost you around $750,000 a month give or take a $100,000 or so! That excludes maintenance reserves or insurance. The margins are so slim these days that to have enough cash in the bank to allow for half a dozen of those sitting around for any length of time would need massive reserves.
There will always be the entrepreneur that will start a small airline ( charter or scheduled) and these will by nature come and go but then I suggest this is certainly the case in all industries and not everyone gets to be Eddie Stobart now do they? How many 'Independent' hauliers went out of business because of rising fuel costs?
You really cannot compare the two businesses as I have already said, the economics are so different.
What I will say is I feel proud to have been part of the airline business, one of the most innovative and safest industries in the World, one that has transported many millions of passengers in comfort and safety over countless years.
Long may it continue and good luck to everyone in it today weathering the storm, keep going because the sun will for sure be back out soon.
Groundhog