What are the plated holes on this PCB for?
Hard to tell from your picture but that pad looks like a fiducial used to help assembly line things up.  A via with no obvious outside traces connected could be a stitching via between planes or between gnd and say outer layer copper flood connected to gnd.  It could also be a via for inner layer traces if say they ran one on the power layer.

That said if it's plated flat and filled, and you can see that it is on both sides then it very likely is a test point