That isn't even remotely how classification or declassification works.

The NGA did not confirm nor deny (typical Glomar response) the nature of the image or if it was the full resolution or downsampled.

We now know it was not sanitized (downsampled) and is from a KH-11 satellite. We also now know both the location of said satellite and some extremely important info like its sensor sensitivities, spatial, radiometric, and spectral resolution, focal length, nadir swath, and even things like lens diameter.

The reason they are declassifying it is because the current assessment is that this particular satellite was burned as an intelligence asset. Everyone knows how it works and where it is orbitally, so can plan around it.

It is a $2 billion asset that was just washed down the drain.

Contractors also do not assess documents for declassification.

Source: a lot of my colleagues have either worked at the NGA or at NGA imagery analysis contractors. I personally do a lot of work using properly declassified KH-7 and KH-9 imagery to extend records of observation for infrastructure development impacts on ecology.