In 2015 my Skype install used >3GB of RAM within minutes of launch. Searching for an uncommon term in chatlogs took hours. I've not been able to open it at all for years because it just hangs on boot.
I'm sure that for the average user none of those are concerns because they're talking with a few dozen users at most, but it had incomprehensibly terrible resource management, which is why all the power users jumped ship the second a viable alternative text chat became available.
If anything, I hope they will treat it like GitHub and let them act mostly on their own, while actually improving the service.
Recent feature additions point to an Enterprise service they are setting up, so this may be a part of their new strategy while keeping the service accessible to free users despite their crazy operating costs.
The same will probably happen with Discord inside the Xbox ecosystem where they want to rival Steam with their Xbox game pass. Discord is the perfect community to do it with.
GitHub and LinkedIn are similarly thriving under Microsoft's wing, without a Twitch-like competitor in sight.
Instagram is more popular than ever since it was acquired by Facebook.
Discord will be fine. Microsoft has a lot of experience in the gaming space thanks to the Xbox ecosystem of services, and in the online chat room space, thanks to Teams.