Do you agree or disagree with Plato's view that there is "a right and wrong way" when it comes to music and that is incorrect to judge music merely by the "pleasure it gave"?

I disagree. The same way that "beauty is in the eye of the beholder," music does not have a set list of rules to go by. Yes there is "bad" music, but what is bad to one person is not bad to another. By judging music by the "pleasure it gives," you are both creating a standard that not all music can, or needs to achieve and you are assuming that all listeners have the same taste as you.