Telegram needs kwayland because while we don't officially support Wayland, unless @livingsilver94 was to start patching it out of Telegram and specifying DESKTOP_APP_DISABLE_WAYLAND_INTEGRATION
, it's just plain easier to give Telegram what it wants, it uses it for its Wayland support. Never know if we'll ever support Wayland in the future, so no reason to not enable it. We do the same for the toolkits themselves anyways.
For SMPlayer, @Girtablulu patched it to look good out-of-the-box on Plasma Edition. That means using the breeze theme.