That's not true. The best evidence that somebody has taste is that they introduce something to you (a band, a movie, etc.) that you've never encountered, but they are correct that you love it. But whatever they chose to share might not be their favorite work of art. They just knew that you would like it, because not only do they have a well formed sense of what they like and why, they can read other people the same way. They can find enjoyment in a huge range of art, because they can tap into what about it is enjoyable rather than reflexively labeling things good or bad. That is the definition of people with taste.