It's a completely circular definition (as far as I can see).
https://en.wikipedia.org/wiki/Duck_typing
A journalist is someone that does journalism, just like a runner is someone that runs. The behavior "doing journalism" is simply reporting on something to an audience.
Certain organizations may get special privileges (press passes), but there's nothing legally binding about them. S citizen journalist is still a journalist under the law.
One of the key points of journalism is sourcing. You'll notice professional journalists, even in the middle of a war zone or natural disaster, will do interviews and try to get a larger context of events. They do this even when they're literally in the middle of an event and documented it themselves.
Anyone that went through journalism school is taught just because they see a thing it doesn't necessarily mean they know or understand what they saw. Their eye witness account is as unreliable as anyone else's so they not only admit to that fact but actively try to get other accounts to find all the common elements and context.
They're saying that they use journalistic work as a standard of who's a journalist... that's circular.
Are you looking for a definition of "journalism"?
If you claim to be a journalist, but can't point to something you've published, then you're not included.
If you claim to be a journalist, and can go "here's three articles I published in a local newspaper (for example)", then you're included.
That seems fine.
Says who? Writing an article is what makes you a journalist. You don't need to be a journalist to write.
This whole "the definition is circular" argument is bizarre, it's like something from Zeno trying to prove that movement is impossible because first you have to move. "So how can you be a mover in order to make your first movements if you're not allowed to be a mover until you've made your first movements?"
It's still an obvious authoritatian intimidation tactic and information suppression tactic to be throwing these people in jail and letting them wait sometimes days for the situation to get sorted out.
A journalist is someone who does journalistic things. What are journalistic things? Well they're things a journalist does.
If you ask Google to define "journalism," you get, "the activity or profession of writing for newspapers, magazines, or news websites or preparing news to be broadcast." See, no use of the word "journalist" in that definition, so no circle.
Don't think that's necessarily circular.