Earlier quoted context omitted.
This is a direct consequence of Skype going from a peer-to-peer model where the servers were just used during call set-up to a far more centralized model. I stopped using Skype shortly after Microsoft acquired it and started streaming all calls through their DC, I could see no other reason than surveillance for it.
It's actually the other way around. "SuperNodes" (elective service as a kind of hub) caused lots of dropped calls and flaky connections because people were trying to do it on bad home connections. Microsoft switched to centralized servers to _increase_ call quality.
Whether that improved quality or not, I wouldn't know, I haven't used skype in quite some time.