A game as large and expansive as Baldur's Gate 3 will inevitably have reams of content left on the cutting room floor. Hearing about these dropped plot threads and cut characters after the fact fosters a sense of longing within us. For instance, the werewolf bard Helia, a cut party member, has plenty of fans, even though she was never in the game.
A Reddit user named AutisticHalsin recently compiled a thread of cut content associated with their namesake character. There's a ton of interesting information in the thread, such as the original vision of Halsin being an older elf, which partially explains other in-game characters referencing his age, which, in reality, isn't particularly old for a wood elf.
There's an interesting tidbit at the end of the thread centred around the shadow druids.
In Baldur's Gate 3, the plot ends after confronting Kagha and the shadow druids. To resolve this quest, the shadow druids must always be slain. Kagha can be convinced to switch sides, or killed along with the rebellious druids.
However, there's circumstantial evidence that this wasn't originally intended to be the end of this plot thread. The Letter to Kagha, found in a hidden compartment...