I don’t think anyone can answer this to your satisfaction without knowing your personal definition of journalism. Because I believe the question you’re really asking is, “Was 538 what I consider journalism?”
When I typed “define journalism” into Google, this came back:
> the activity or profession of writing for newspapers, magazines, or news websites or preparing news to be broadcast.
So yes, 538 was journalism by at least one definition of journalism.
Here’s one more definition:
> Journalism is the activity of gathering, assessing, creating, and presenting news and information. It is also the product of these activities
When I typed “define journalism” into Google, this came back:
> the activity or profession of writing for newspapers, magazines, or news websites or preparing news to be broadcast.
So yes, 538 was journalism by at least one definition of journalism.
Here’s one more definition:
> Journalism is the activity of gathering, assessing, creating, and presenting news and information. It is also the product of these activities
Another yes! We’re 2 for 2!