Sure, it is fair to note, and I think it's actually a pretty good point now that you've clarified it a bit. (I speak as someone who's currently using Python at work but Perl for my own things.)
However, it's a manner of how you present the comment. As you originally stated it, it pretty much sounded like "He's Doing It Wrong", which didn't add very much to the discussion. In my opinion, a much better way to go about it would have been something closer to "I think it's worth contextualising his comments. It is likely that the style in which was coding was more in line with earlier styles that are not used as often in 2011. While Perl is obviously still Perl, more recent styles do help alleviate some of his concerns."
Now, this clearly still isn't a perfect comment, but it, or something more like it, would serve both to clarify your position and to allow for discussion based on it, if people were up for such discussions.
But, again, I feel the need to reiterate that I was not one of the people who downvoted you, so I'm only guessing as to the most likely reason for the downvotes.
However, it's a manner of how you present the comment. As you originally stated it, it pretty much sounded like "He's Doing It Wrong", which didn't add very much to the discussion. In my opinion, a much better way to go about it would have been something closer to "I think it's worth contextualising his comments. It is likely that the style in which was coding was more in line with earlier styles that are not used as often in 2011. While Perl is obviously still Perl, more recent styles do help alleviate some of his concerns."
Now, this clearly still isn't a perfect comment, but it, or something more like it, would serve both to clarify your position and to allow for discussion based on it, if people were up for such discussions.
But, again, I feel the need to reiterate that I was not one of the people who downvoted you, so I'm only guessing as to the most likely reason for the downvotes.