Curved median segments 
If the median segment (B) has been shaped with geometry nodes, it is not straight and cannot be used for determining parallelism. Instead, draw a straight segment connected at the same in and out junctions (where in-segment (A) junctions with the median segment (B) and where the median segment (B) junctions with the out-segment (C)). Check the angles using this new straight segment, and delete the new segment afterwards.
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Be sure the junctions are not locked above your rank. Otherwise, drawing a new temporary segment connected to locked junctions may produce a save error even if it is deleted prior to saving. |