Understandable choice, given that Skype is pretty much redundant with Teams. Back in 2004-2005 Skype was really hyped because of free voice calls through the Internet, but few days later several other messaging apps incorporated that feature; Skype's thunder was stolen. Also its inconsistent branding was a problem: there was Skype for Business that later became Lync, ultimately becoming Teams. Skype kind of became forgotten and obsolete.
Seriously though, Skype is a good example of how MS butchers products. I mean, I never loved Skype but it worked and was the defacto video calling platform of the masses. If they had their shit together, even a little bit, then Zoom would never have taken the market.
I don't really like zoom either, but its better than Skype.