Sounds like that discord aspires to be a safe space but they don’t think they can account for all users behaviour nor can guarantee that a user won’t encounter their negative triggers. This is sensible because it’s a social media - wouod probably be different for a organised support group or club - both of which could be hosted on discord, to be fair, but the main gist of this is that if User B says something rude or triggering to User A, the mods cannot instantly detect and remove it.