Your first example is a very fair point, I wasn’t thinking about people who basically stumble into something important and decide to publish it. But unless something very odd is happening, that will not happen over and over again to the same person. More likely, it may happen to them once and then they’ll decide they want to become a regular citizen journalist, as you say, and then they will need to do a lot of work (with associated costs) even if they aren’t getting paid for it. Which would be another example of my first suggestion.
For the rest, I realize that there are plenty of examples where people provide accurate and timely information without charge (a lot of Lemmy is, and hopefully will continue to be, an example of that!). But those people are, for the most part, doing volunteer work, which is very valuable and healthy, but nevertheless is still work (that has costs).
I was not claiming that free goods, or free news in particular, “can’t” be worthwhile. Just that it implies that someone is supplying so much that goes above and beyond what a lot of people are trying to get that there is no need to charge for it. That can be an example of something very charitable and wonderful, or it can be an example of someone trying to push something that most people (rightly or wrongly) think is not very useful.