When I worked as a Supervisor in a Movie Theater I learned that this is true.
Stats show that only 1 out of 10 people will actively stop what they are doing to compliment something good. (IE: "Hey, I just wanted to let you know that your Movie Theater is awesome!" in person or via an online review) Most people that enjoy something will simply come back to enjoy something again as their way of signaling a good experience.
Stats show 3 out of 10 people will actively stop what they are doing to mention disappointment or dislike. (IE: "The experience was just dreadful... The sound was off and the threater was WAY TOO COLD!" in person or via an online review). Most people that don't enjoy something will simply return less or not at all as a way of signaling a bad experience.
In management, we were trained to stop and take notice of ANY feedback Good and Bad. It's too rare to not spend the effort paying attention to it.
That being said, you should expect 3-to-1 ratios in terms of negative-to-positive feedback based on the above description of how often people make their opinions known. Online forums are absolutely shaped by that ratio and it's one of the reasons why "the silent majority" are spoken of as a meme. While our public facing feedback might be more negative then positive our play-rates are steady and our game continues on after 7 years.