Neuroradiologist here. 👋🏻

The short answer is not necessarily.

I think the main reason for this difficulty on the imaging side is that the brain is such a highly tuned, precise instrument that doing small areas of microscopic damage (below the threshold of medical imaging to detect) can still result in noticeable dysfunction (so a brain can look normal on MRI but have damage too small to see). Secondly, the MRI appearance of chronic trauma overlaps hugely with other, more common conditions.

In a research/university setting there is improved ability to detect some of these cases using advanced or experimental techniques that aren’t common out in the community setting, but even so I would wager that there are a significant number of cases that fall into the “looks normal” category.

What the VA told me was that blast injury is like CTE in a football player's brain. They aren't detectable before death because the damage is widespread at the microscopic levels. Basically trillions of brain cells connections that didn't heal right each time you get a concussion. It's not one big thing that shows up on imaging. They have to put slices of brain on a microscope to see the damage.

And no that did not make me feel good about getting older...

maybe the interpretation of the results were not done carefully.

That's a weird assumption to make, without any facts in evidence to the contrary.