I'm pretty sure it's something of a One Mario Limit effect. Like for me, sometimes I'll have trouble mentaly distinguishing Oscar the Grouch and Oscar Madison: both grumpy, irritable characters that basically live in garbage - if I hear just the name Oscar, either one of them will pop into my mind.
This is one of the reasons why one common naming process for my own characters is trying to think of names you don't hear very often, at least for fictional characters.
This is one of the reasons why one common naming process for my own characters is trying to think of names you don't hear very often, at least for fictional characters.