I've rarely seen this comment on hackernews about wikipedia. I think you may have been thrown off by the use of "liberal" to think it's a right-wing critique. Incidentally, the complaints I'm used to are that "they keep deleting the thing that I'm involved with that I think is notable" "they won't let me edit myself even though I'm an expert on myself" and "weird editors squat articles."

This is a "wikipedia is completely western and whiggish" critique.