First, you have to establish and define what you mean by "subpar" quality of audio gear in today's market. Is this based on an opinion, electroacoustic measurements, listening tests, etc? What evidence do you have that audio gear in general has gotten worse?
For example, the popularity of mobile/portable audio means more people today are listening to iPod/iphone/internet-sourced music over earbuds, laptop speakers, ipod docking stations; these playback systems may produce lower quality sound than similar listening experiences in luxury cars equipped with high-end audio systems, and home theatre/listening rooms. So, you need to clearly define what you mean. I would quantitatively define lower quality in electroacoustic terms that are correlated with poorer sound quality. For example, the speakers have less bandwidth (e.g less bass), irregular frequency response, lower SPL output capability, poorer stereo imaging, higher distortion at a given SPL, etc.
The popular press has spread the idea (misinformation) that the prevalence of "subpar" quality of audio gear and data compressed audio files has resulted in Generation Y preferring lower quality sound. This theory has never been really proven but I recently did a
controlled listening study with 58 high school and college students and some 150+ Japanese college students that showed they prefer higher quality file formats and loudspeakers when given the opportunity to compare them to lower quality options. If kids are buying crappy audio systems/music formats it's not because they prefer their lower sound quality. It's probably due to cost, convenience, portability, or they are simply unaware that there are better options out there. The audio industry has done a poor job of educating and marketing better quality sound to consumers.