Earlier quoted context omitted.
Single data point: I open Skype for one occasion: Monday night, gaming with friends that - for the lack of a better term - "don't know better" (I'd prefer TeamSpeak or Mumble for Gaming - or any other voice chat that doesn't require a G+ account really). Skype is slow. Ugly. And worst of all: It shoves ads in my face on multiple levels (popups, banners etc). So far I keep it for this weekly use case, but I hope that…
Your Skype shows ads? I've never seen ads on Skype.
There seem to be ways to make that go away (null listing hosts either directly in the hosts file or - on Windows - in the Internet Connection Settings). Maybe. Before I'd use that app for anything of value, outside of my Mondays .. I'd try these approaches.