yes, but I’m not talking about the authors per se. I am talking about the fans.
If YOU read a book, you have the right to like or dislike it and talk about it and say well that book sucked. An you also have the right to be vocal about it.
The same goes for fanfiction. if YOU read fanfiction you have the right to dislike or like certain pieces. For example, there are people that absolutely can’t read angst. I personally can’t read anything that is non-con.
I can have my favorite authors, and have authors I cannot read. I can also say “well that fic had horrible characterization, the story was off; I hated it.” It is my right as the reader to have an opinion, and I can be vocal about it if I so wish.
Also remember they are not picking at specific authors (as far as I’ve seen.) They are just giving their opinion. Which, to my understanding, is; There are some great fics out there but for the most part they haven’t been characterized correctly, and that makes me sad.
That is not something bad. Being critical about what you read is not bad, having an opinion about what you read is not bad, especially when (as far as I’ve seen) they have not done it in a demeaning way at all.