Well, Skype the brand was botched, but Skype is basically what powers Microsoft Teams now. Which is widely successful due to it being bundled with Microsoft 365 (also Teams is pretty decent compared to the comp).
Interestingly, it looks like Teams was at one point code-named "Skype Spaces" - a name which occasionally appears in Teams deep link URLs.
* see this job ad here: https://careers.microsoft.com/us/en/job/834482/Site-Reliabil...
The Teams comms/meeting stack was its own thing - an evolution (or frankenstein's monster mix) of Skype for Business and Skype Consumer technologies. That is one of the reasons why Teams did not have interop capabilities with SfB at launch.
Side note: The Skype for Business communications stack is a descendent of Lync/Office Communicator was completely separate from Skype Consumer (only thing it shared was branding).
Source: worked on Teams