The number of completely wrong generalizations about distributions I hear by people being sincere prevents me from reading that as anything but one. People saying "only Ubuntu X" when they really mean "only debian-based X" is one of the most common mistakes I hear.

If I did misread it, that's an even worse thing to say. If a person is in the position of asking if ufw will work on CentOS, it is downright mean to give an answer that requires them understand esoteric particulars of the debian bloodline.

I don't know if I would call the package management system of debian esoteric in a conversation comparing distros. I will agree that the wording was a bad choice.