For the last 30 years there have been a parade of "chat" programs such as CuSeeMe, ICQ, AIM, Paltalk, Skype, Google Talk, Google Hangouts (and I think four other chat programs) and Facebook Messenger, MSN Messenger, Lync (I think I spelled that right), HipChat, Slack, even "Skype For Business" and "Microsoft Teams."
In the open world the story is more dreadful, as IRC is a backwater and the open XMPP protocol is more popular with cops, soldiers and spies (just pipe your XMPP messages into Lotus Notes...) than anyone else.
The one constant is that you can't plot a steady curve of products getting better in time (like the underlying computers, network, etc.) Instead it seems like something starts out cool (like Skype at the beginning) and then deteriorates, then it's like "Cool, Zoom! It works as well as Skype used to work"...)
I think the market for these programs is not a healthy competition but rather these are a backwater in the big battles over platforms. (e.g. Facebook Messenger is like AIM except FM is tied to FB and AIM was tied to AOL.)
If the euros wanted to contribute something positive to the world they would kick out proprietary chat programs and get people to use a profile of XMPP.
Skype is mainly for person-to-person calls, but that tech has been commoditized and made into a one-click feature of Facetime, Facebook Messenger, Instagram, you name it. Downloading a separate app just for video connection seems excessive these days.
If MSFT had just left everything alone I'd still be using skype regularly.