I had an issue like this yesterday on a Northern service where the guard had been, for a good ten minutes, standing with some friends chatting not far from me, while some idiot played his phone out loud really loudly, even after I had asked him to turn it down (and he did, but then later back up again) and someone else intervened too. I said out loud to the other passenger but with the intention of her overhearing something like "well, you'd think the guard would deal with it seeing as she's stood there" and she seemed more annoyed by that than the evident breach of Bylaw 7, coming over and saying very bluntly "well if you'd asked me I would have done", to which I said "well can you please?" and she did, and it remained off for the rest of the journey.
I do understand that some staff fear such encounters and so won't intervene, but on being prompted she seemed happy to do so. So why not deal with it proactively?
It wouldn't surprise me if she felt compelled to intervene after you complained, even if that could mean putting herself at an elevated risk which she would otherwise not do normally, but not knowing her it is impossible for me to say why. There are of course bad apples, as with all professions, and it could also be the case that she was having a bad day and did not feel mentally strong enough to challenge them. We are all human. I may let go of certain issues on some days which I would happily challenge on others.
I would say you are quite fortunate that she intervened. If I had already decided that I was not happy with the risk of the anti-social behaviour potentially eslacating, you would probably have got shrugged shoulders, and a suggestion to please move into the next coach. After all, my primary responsibility was to ensure everyone gets to their destination safely, and that includes the troublemakers too. If there is a risk of such situations deteriorating and imploding, then a bit of noise and discomfort very much pales into insignificance.
Personally I prefer passengers to not challenge each other directly, as these often don't end well. Wrong things can get said or right things get said in the wrong way, tempers fray and things can get out of hand quite quickly. I tend to find a quiet word from myself working well, if a passenger raises a complaint about their fellow travellers directly with me. Unfortunately if quiet words have no effect then there is very little else I can do, nor will passengers taking matters into their own hands in those cases.
I'm not sure that's "safe" if the public information is stating the deviation from plan, and the traincrew don't receive an SSO. That would put both public and traincrew in an unreasonable position.
It really is no different to other situations where trains fail to stop at an intended station due to an error/misunderstanding/omission/comms issues. These only happen very rarely and there is no perfect "one size fits all" solution. Departure screens can be wrong, same with apps, especially during severe disruption. Services and stops get added/cancelled/reinstated at short-notice and that is just the nature of the ever-evolving operating environment. The bottom line for the crew is that unless they have solid personal confirmation otherwise, they stick to their booked schedule. That is a nationwide industry baseline. On the ground, driver and guard are the ones responsible for the service and interacting with passengers, so consistency is important so there is no confusion which set of conflicting information takes priority.
Traincrew also need to remember that they are part of their employer's customer service, and to use (and be provided with) effective means of communicating uncertainty - I've taken "I'm sorry, I know that's on the board but I've not had that confirmed yet; please wait" as an honest statement of position.
It is indeed all about communication. Showing empathy and giving passengers the impression that you care about their concerns can definitely help in conflicting situations. That said, again it will depend on the exact circumstances at the time. For example, if this is raised as an issue to me five minutes before departure I will happily call Control/driver to confirm, or flag down the dispatcher. Less than 2 minutes before departure, on a proceed aspect, then unless I get a call from Control/driver/slip from dispatcher, I am not delaying the train to check or be otherwise distracted from dispatch duties. The train calls at booked stations.
I get the logic, but disagree. While there will be exceptions, quiet calm enforcement by staff at all times helps create the expectation of the right behaviour. Leaving enforcement so it's by exception only just encourages the poor behaviour, while making the stakes higher when someone does enforce it.
Quiet enforcement only works to a certain degree, so does regularly patrolling the train, beyond which you are pretty much by yourself and support is often far away. This isn't anything a guard can fix.
You tend to find traincrew get a bit funny about people interfering with their train. I nearly got into a heated debate with a driver travelling on my train (a 158) a while back. I was having a bad day as it was, it was warm and the unit had been shut down for an hour.
I had to be quite stern with an off-duty staff member once when they used their own T keys to open several windows in the coach, when a struggling aircon was slowly working its way to optimum temperature. I had already passed once and all the passengers were happy to either stay or move to an adjacent coach. They boarded mid-journey and asked for a free ride, so knew exactly where I was. Doesn't take much to come knock on the cab door.