Every tire that Ive seen on a semi trailer that is flat makes the trailer wobble. How can that not be felt? Cant you still drive for a while when the inside tire blows? In my mind, with no expirience driving a semi, the driver is on a paid schedule and doesnt want to spend his time with a repair if he can still get to his destinantion. A paid schedule that often results in lack of attention securing his load. Being a driver wouldnt you agree there are a lot of yahoos out there who just care about getting from point A to point B?
If the trailer is wobbling you will feel it, most flats will not make a trailer loaded with 40,000 wobble. You can still drive on a blown tire, but run the risk of it causing further damage to the trailer, or others. Some drivers are paid by route, others hourly, a majority of commercial drivers are polite and do a good job. There are yahoos out there, just like there are in any other job, or even the motoring public.
Again, I suggest you ride with a driver for one day, amd I think your questions would be answered and you may feel differently.
By the way, the driver in this story, is one of the 5% of idiots. If he got a citation last year for not securing a load and did the same thing again, he needs his license pulled and live up to any legal action that comes his way.