While Microsoft has put a lot of work into the People Bar in Windows 10, it seems that it's going away soon, as is reported by Albacore on Twitter. Apparently, future builds from the 19H1 development branch will see a deprecation notice upon using it.
Of course, deprecated and removed are not the same thing. The feature will continue to ship with the OS for the time being, but new features won't be added, and eventually, it will be removed. That means that when Windows 10 19H1 ships in the spring, it should still have the People Bar. As far as any update after that goes though, it could be removed.
The People Bar, also known as My People, took the user's contacts and provided shortcuts to messaging applications and such. The big problem is that most services don't support it. For most contacts, you'll just see a Skype and an email link.
While Microsoft hasn't officially commented on the rumor, it should come as no surprise. It doesn't seem to be the most popular feature in Windows 10, and most will probably never even realize that it's gone.