Depends on the tone and whether it's being shouted at an individual. If someone shouts the second one at you, responding politely by asking them to lower their voice will very quickly differentiate between complaining about the situation and abusing staff.
The latter isn't a very good way of dealing with a person who is justifiably angry. With some it will cause them to
get abusive even if they weren't before. The absolute worst thing you can ever do to an angry person is to tell them to calm down - the first step to defusing a situation is empathy in most cases. Note that empathy doesn't mean giving them what they want, but it does mean acknowledging that their upset is justified, even if it's brought on themselves and there'll be no resolution without them paying a chunk of money.
"Can you just calm/quieten down please" could very much go either way.
"Yes, I can see the problem there, can we just talk about it and we can see how it can be resolved" might be more effective, while not actually conceding anything (the resolution could for instance be the full price sale of a new ticket if the reason for the anger is having missed the train on their Advance).
Some staff genuinely aren't very good at this and thus will experience a lot more abuse than others. TOC training really should be covering this kind of thing in some depth - call centre training certainly does. And staff consistently doing it badly despite training probably need to be considered for other non-public-facing roles. (You can probably easily tell by comparing complaint numbers and nature between staff in the same role in the same location).
Of course anything physical is abuse and is likely to justifiably move onto BTP attendance. Touching another person without their express consent is never acceptable, and getting overly close to them is certainly aggression.
But there are some staff who will sell that £300 Anytime or issue that PF and get a "thank you" back, and there are some who will either fail to sell it or at least get fingers stuck up as they walk away, and that wholly depends on how they respond to someone who has a reason (regardless of whose fault it was) to be angry.