My observation is if a thread is 99% negative in a very strong way about a mistake or program change you'll see an official comment from DL. Example, the SNAFU last week where Medallions were seeing higher fares from the search engine than base customers.
When threads split up into Red Tail V Blue Tail it guarantees no comment or action from DL. Why should they do anything, enough of the customer base is willing to take it.
When DL is obviously breaking a regulation you won't hear anything either. For instance the threads over DL's long standing policy of selling A fares that are really poorly disclosed coach fares with time of booking upgrades (PAX end up paying hundreds more, only to be seated in coach when IRROPs happen). There has never been an official statement from DL on this. And I doubt there ever will be until the DOT issues fines.