First off this would not be a ticket to guantanamo it would simply be more scrutiny.
Secondly the other sources are likely the main tool and the credit check merely added to the indicators.
No one item would be the key trigger but all of the profiling put together would trigger a more intense check.
The roads would probably not be perceivably more crowded as the hundreds of thousands of people flying would be a small fractional increase in road traffic nation wide.
I am simply trying to point out that the article is politically motivated and bears extremely few facts as to the usage of the information gathered. It is an overly melodramatic personal opinion piece. The conclusions of this are disingenuous.
If the information gleaned from the credit check includes large purchases of nitrates or tremendous life insurance policy or a series of uncharacteristic purchases beyond ones means then perhaps that would be a valuable addition to the FBI, CIA, IRS, INS, Police and inter poll profile generated.
I do not believe that even a red would exclude you from flying it would simply trigger a cavity search