Kevin Kofler, who has long been involved in KDE packaging for Fedora and advancing KDE on Fedora, he is stepping down from their KDE SIG and from co-maintaining all of the Qt/KDE packages he maintains for the distribution -- except for the few packages he is the upstream maintainer of in the KDE world.
Besides taking a lot of time and work to maintain, he's having a hard time keeping up with the latest KDE project changes and he is unhappy about the state of the KDE desktop on Fedora in some regards. For instance, he's unhappy that Fedora is more clearly GNOME-focused, the Firefox web-browser is the default for the Fedora KDE spin, and how Fedora 23 KDE is "easily the worse KDE spin we have ever released."
Beyond just the Fedora world, Kevin is also unhappy with upstream in some regards over the quality of the current upstream KDE stack. He notes big upstream issues with Akonadi/KMail, the reports about the quality of KDE Plasma 5 being in poor shape, and other items that led him to depart from the Fedora KDE SIG.
You can read his resignation in full via the Fedora KDE mailing list. While he will still be doing other Fedora work, Kevin Kofler is also planning on spending more time with Kannolo, a pure-KDE Fedora remix.