This is misleading. They deleted the original Justice for Karlach thread because:
1. They reworked their feedback system to cut back on the number of threads since discord has a limit.
2. That thread kind of turned into a cesspool of threats and transphobia so the original poster requested it to be deleted.
There is still an open and active Karlach thread in the archived feedback section, and people are still free make new Justice for Karlach feedback posts. You just can't comment on new feedback posts since it usually just devolves into unrelated conversation. There has been no sign from Larian that they are hostile to Karlach related feedback besides putting her in the frequently requested feedback section.