The person who said that might have meant that it is bad to learn from if you want to learn Japanese seriously. Lots of Japanese learners confuse anime Japanese with real Japanese, and that probably annoys some people. I honestly have a hard time understanding the point of anime, but it is obviously such a popular industry that it has influenced so many people from around the world. if it was not meant to be watched, I don't think it would be made on such a large scale.

Hey Anime Nerd00. There is nothing wrong with watching anime to help training your ear. Anime is a great way to help you learn some phrases, find distinction between words and so much more. Plus, animes have some pretty great songs to listen to. In short, I don't think it is harmful to watch anime and train your ear and help in word distinction.