The company I work for have a rather enlightened policy of being totally up front as to the reasons for a delay and this is usually “pushed” via app to the customer.
In my experience, customers are much more understanding the sooner and more completely you give them information. Drip feeding of negative news is the worst situation - I prefer to outline worst case and everything from there is an improvement.
Ultimately I think it is an organisational culture thing whether ground staff, operational staff and HQ communicate well with eachother and with the customer. If the gate staff are having to be cajoled then there is already a problem. It goes without saying that treating all colleagues with respect pays far greater dividends in terms of extracting accurate information than going in like an ill tempered hippopotamus.