When Microsoft acquired Skype (the company), it was clear they would kill it. Skype had previously been bought by eBay, for which it served the purpose of entering a new market. Then, it was bought by some investment funds, for which it served the purpose of making money. However, to Microsoft, which already had its Windows/Live messenger (which copied Skype’s homework anyway), Skype served no purpose except to remove a competitor. They did not have a reason to develop it.
I’m surprised, in some ways, that it took almost 15 years for it to die. If Microsoft absorbed the Skype tech in 1 year and rebranded/reskinned Live Messenger to look like Skype, they could have been done with it in 2012.
Now, they are retiring Live Messenger and Skype. Two technologies have become zero. It is interesting that they chose to go this way.