A quick google search and I found the article you're referring to.
https://www.washingtonpost.com/news/innovations/wp/2016/06/01/what-you-are-doing-online-and-other-top-findings-from-an-exhaustive-study-of-the-internet/
Even assuming 1010data's information is correct. A speaker is a terrible way to categorize Echo. I would suspect most people only buy it for listening to music as a secondary reason. It seems to me that the reason most people buy an Echo is for asking questions and home automation, much like Siri and Apple's homekit. My phone contains a speaker as well, but I'd never describe it as such. No doubt some people will use them for listening to music, but they were never going to care about audio quality anyway. If they didn't buy an Echo, they'd just buy some other Bluetooth speaker.