Via a user at Summit:

"When we synch with Crowd and a user is flagged as deactivated in Crowd,
they are not being removed as a Crucible user. We want that users data to stick around for auditing, however we need to free up licenses when people leave the company."

This could require a new option on synching with how to deal with deactivated users in crowd.

Current behaviour is possibly the user becomes 'deleted' from Crucible/FishEye when they are deactivated from Crowd. This needs testing/investigation though.