[imran-iq]

I think (and I could be misremembering here) is that Emby started off as C# and both Plex and Jellyfin are forks of it. Also a lot of folks in this sphere seem to be on windows as their primary platform, and C# along with visual studio is pretty on that stack

[seabrookmx]

Plex is a C++ app and actually a fork of XBMC/Kodi, although that was so long ago there's probably no resemblance.

Jellyfin is an Emby fork though, yes.