Sony's billions in lost revenue came from other ventures than their gaming division. The walkman went down the toilet due to the iPod, Samsung & LG could compete with their quality in HDTV, Apple & Samsung cornered the smartphone markets, they pulled the plug on their PC division due to all the competition of quality laptops etc. Regardless Sony is still a respected Forbes top 100 company in the world. If you buy anything Sony from a HDTV to a car stereo to a PS4 you know you are buying Quality.
https://www.youtube.com/watch?v=mAobb8_SzHY
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