It's arbitrary. If it was a vector, maybe, but that would only be true as long as maintained as a vector, meaning never printed or scanned.
If the scanning or processing software set a threshold for removing all shapes and applying a stroke of a certain size, that could make sense but I would expect to see more fill removed elsewhere and this would concern me that the scans were being automatically tampered with and I would not trust the process without a good explanation.
It's arbitrary. If it was a vector, maybe, but that would only be true as long as maintained as a vector, meaning never printed or scanned.
If the scanning or processing software set a threshold for removing all shapes and applying a stroke of a certain size, that could make sense but I would expect to see more fill removed elsewhere and this would concern me that the scans were being automatically tampered with and I would not trust the process without a good explanation.
Looks like everything wider than 2x the stroke to me? The triangles, the "sign within the box" text, the border around the signature box...