No, not really.
You can't compare Cohen to Hitler, and really, it's JUST a name. So what if Jews doesn't use it themselves? Shouldn't stop anyone else from using the name. And if Cohen is offensive, shouldn't other religious names be that as well? I wouldn't be offended if anyone named their son Priest, and I wouldn't be offended if someone named their kid God either (even though I'm an Atheist). I think it's a bit stupid, but not offensive.
And besides, Cohen is a pretty common name nowadays.