“The gemara (Shabbat 62) allows a man to wear a signet ring in reshut harabbim, as it is common for men to wear those. Other rings, however, are not normally worn by men, and they thus cannot be considered a garment.”
B’zman hazeh it IS normal for men to wear wedding rings (and nobody wears signet rings anymore unless he is a king or something). The only question is whether or not that would be chukas hagoyim.