I think the relevant point is you shouldn't malign a project without justification. I'm really interested to know why the person thinks the kernel is technically deficient and since they didn't include that information, the comment itself is a big letdown. Not including any information on why the kernel is bad is about as informative as a comment simply saying "linux is teh rad." (I think it's troubling so many of those types of comments get upvoted.)

I agree with you on at least one point though, whether or not the project is large or popular shouldn't be relevant to the voting.