Carbonic acid is a weaker acid than acetic acid, which is a fundamental chemical fact based on their respective acid dissociation constants (pKa values of roughly 6.3 and 4.8, respectively).
The relative acid strengths of carbonic acid and acetic acid are fundamental chemical facts taught in standard chemistry curricula, dictated by their known pKa values. None of the retrieved papers specifically test or evaluate this direct comparison, as they focus on atmospheric chemistry, protein structures, and drug design.