Well, OK maybe Richard was a poor example. What I'm saying is: some Richards go by Rich, but few goes by Chard, and certainly nobody interprets Richard as a combination of two name components "Ri + Chard" (or "Rich + Ard"). The probability a typical Korean would consider their given name as a combination of two parts is probably higher than that of Richards, but not much higher.

Maybe a better example is Anderson, which historically meant "Anders's son", but few living Andersons would consider "Anders" an acceptable way of writing their family name.