Mass surveillance was easier when anyone, including the NSA, could run a supernode. Microsoft had to run its own supernodes because usage changed from most people running Skype on desktops, which could be supernodes, to most people running Skype on phones, which can't. At that point, it hardly makes sense to push new supernode functionality for multiparty video calls and other optimizations to end users to handle a small fraction of calls when updating your own servers is much easier.
WebRTC will happily set up a P2P video call with better encryption than the old Skype had if all you need is a 1-1 call without NAT traversal.
