The Echo Studio seems to try to keep up with the Apple HomePod and Google Home Max. It also seems to try to wedge out Sonos and other high (low) end speakers. The benefit is native Alexa integration and more potential integrations with other Amazon devices.
Voice interaction when music is playing from the device is difficult. It requires digital signal processing chips with acoustic echo cancellation (AEC). This becomes more difficult as the the echo and signal match the same power. CNET reports that even at high volumes, the Echo Studio performs well, which is a difficult fete.
The problem is compounded when you have multiple speakers setup and a subwoofer playing music. If Amazon did its job right, it could mean that the devices can respond to voice when it would be difficult for others to hear you. Amazon already uses cloud verification for wake word, which means it could increase sensitivity to wake up comment if music is playing. The only annoyance of a false trigger would be the audio ducking.
It seems the device increases the distance between its microphones. This might create beam forming array that could be better at picking out noise, especially when it applies AEC to the signal. If the device is synchronized with other Echos, it could mean an even larger mic array.
Such a device makes sense over third party speakers that incorporate voice, especially Alexa Built In devices. It seems Amazon has learned from other players in the space to build something better.