No, it shows that journalists write for a different audience.
"What's easy to read is news articles that are based on scientific papers."
That shows journalists wrote for a wider audience.
The articles that journalists write are considered better by laymen, but typically, they provide insufficient information for experts to see what exactly is new in the article and/or simplify so much that experts find the information presented downright wrong (search HN on battery or fusion break-throughs for examples)
But yes, it is true that quite a few scientists could do with a good editor that helps them write text that is easier to understand for experts. The current citation-happy culture doesn't help there, with abstracts that have more "(Newton, 1754)" phrases than actual text describing the work done.
The reason they are so easy to read is that the journalists tend to simplify and generalize the results to such an abstract level that the 'research' they present in their article bares only passing resemblance to the actual research presented in the actual paper. And that's assuming a best case scenario where they don't simply misunderstand the whole thing.
All that being said, I agree that most papers could do with a good copy editor. Fortunately there are hundreds of freelancers willing and able to do that and many universities even have someone on staff or retainer that can help out.
Making a standard research article readable to the lay audience, even if it is also educated to some degree in the field, would double or triple its length.
Also, once you're past the abstract, it's still heavy going. Compare that to text books which tend to be a bit easier to follow.
I'm not saying these are the answers. Just highlighting the problem of readability. That seems more serious than not having a space between a unit and a number, or a formula having a disproportionately big fraction. Even more important than spelling and grammar which humans can mostly correct as they go.