Yeah, the correction re: prototype inheritance is a good one.
That said, there is a qualitative difference in what we call 'classes' in those two environments, which is part of why I think there's confusion. Class in Java is a fairly different concept than a Class in Smalltalk, Ruby, or JS.
That said, maybe the difference here is how often the janky metaprogramming of classes interferes with day to day peogramming; a java programmer might have never seen this stuff, moreso then a ruby one?