As either example grows in complexity, they both wash down to a check and a call to another method to do the heavy lifting. In that case, the length of the methods will not grow apart from each other heavily.
And let me be clear. My gripe is only with the example. Not the idea. I happen to like pattern matching, but have never used it like those. Usually I use it to tease apart data by parts. (though, to be fair, I have found I use it less than I thought I did. Not sure why...)
I suppose it's a matter of opinion, but to me the comparison of these two snippets is nowhere near "a wash". The readability of the former is leaps and bounds ahead of the java version, and it will only be more apparent as the example grows in complexity.