In fact, I disagree with quite a few responses mentioned in the paper.
I think that many of these statements depend on the point of view of each person, for example when saying that certain languages are more difficult I think this is true, I know many people who speak more than 3 languages, and they think it's easier to learn certain languages than others, and on the other hand to say that some accents are better than others also I think that depends on the taste of each person and on the sounds that each accent can transmit to the people. For example is more pleasant for me the French accent than the German accent