Based on the discussion in this Slack thread, it seems that deleting a table involves durably writing the file data to disk first.

Storex team is actively working on SPM-3313, where we are adding a new WiredTiger instance to mongod exclusively for temporary tables. In this case, we do not need to preserve data after a restart, so we would like table deletions and WT_CONNECTION::close to be very fast.

Is it possible to make table deletions a constant-time operation?