I don't think living in a happy city is boring. In my opinion, a happy city means that people are friendly and there are lots of things to do like festivals and community events, which makes life fun.
幸せな街で暮らすことが退屈だとは思いません。幸せな街とは、人々が親しみやすく、お祭りやコミュニティイベントなど、楽しいことがたくさんある街だと私は思います。