I'm not exactly sure, I've noticed the same thing.
Go appeared a few years ago, quickly became pretty well-known, and continues to grow in popularity. Maybe it's seen as "threatening" to older projects like Ruby and Python? The most vitriolic comments always seem to come from Ruby, Python, and Rust partisans. Of course, I'm not sure why they're so threatened by it, they themselves explain in great depth how the lack of generics or exceptions will prevent anyone from writing any real code in it, or even trying to in the first place!
Go appeared a few years ago, quickly became pretty well-known, and continues to grow in popularity. Maybe it's seen as "threatening" to older projects like Ruby and Python? The most vitriolic comments always seem to come from Ruby, Python, and Rust partisans. Of course, I'm not sure why they're so threatened by it, they themselves explain in great depth how the lack of generics or exceptions will prevent anyone from writing any real code in it, or even trying to in the first place!