I agree with you that the mere fact that many people like a certain show (or certain actor as I've seen) should not make any person like that same show or actor less. If they do not legitimately like the show, that's fine. But, I've seen many cases where one liked a certain show, then disliked it because of its popularity.
However, I do somewhat agree that too much of anything causes detestation. For example, in the months leading up to the screen adaptation of Rent, the television stations were ridden with advertisements. Many of my friends began to not want to see the movie simply because of these numerous commercials. Even I, a fan of Rent years before the movie, became unexplainable nauseous whenever I heard even a small bit of "Seasons of Love" during that time.
So, the point of my rant - yes, in my experiences, too much publicity does seem to take a negative effect. However sad as it is, it does happen, and it is quite a shame.
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