This reminds me of how Yahoo Messenger was silently a significant part of the oil trade, and its shutdown may have subtly made the industry more opaque: https://www.reuters.com/article/technology/oil-traders-prepa...

I have no doubt that we'll see stories about niche industries still built on the backs of Skype that are scrambling to adapt. Nowadays, I suppose it's likely a rounding error compared to other ways that geopolitical forces are disrupting various industries... but we should all be aware of the implicit commitment we make to users when releasing any B2C service, and how people will build entire livelihoods around the simplest of services in ways we can't anticipate.