Many people require grief counselling (or bereavement support as it can also be known) for "normal grief"
What I meant was that most people don't need therapy to get them through normal grief if they have support from those willing and able to give it, as the colleagues who seek the bereaved person out seem perfectly willing and able to do. It seems like some people are uncomfortable with other people's grief as if it's abnormal. It isn't. It is also normal to deal with it privately. It just means there are a range of normal responses.
I don't think those people who are uncomfortable with others' grief should expect them to hide it away and take it to professionals though as so many have suggested, when it's a normal human feeling.
Some people may prefer to take it to professionals for a range of different reasons but that doesn't mean everyone should feel they have to.
Empathy, sadly, is lacking in many people, so no, not a natural human response. Many have no clue how to be emphatic.
And many people do, including the colleagues who have sought out the bereaved person to support them. They don't need special training for this.
Just look at this thread. People have made all sorts of unempathic comments about the 24 year old. We only have the OPs comments on what happened. The 24 year old of able to give their view may have a different perspective.
People are allowed to form a view based on the information given. This happens for most threads. You're also making assumptions, just like everyone else. Those who have a different view from you are just prioritising a bereaved person over someone who's triggered by a bereaved person. Without any further information, that's the situation. The 24 year old may have had traumatic losses, as many people have suggested based on their own experiences, but that's a much bigger reach than to say the bereaved person is 'trauma dumping' indiscriminately when the OP is explicit in stating that's not the case.