"We don't know what it does, but junk DNA is a real thing, and that's one possible explanation" is a lot more reasonable. And I think that's a more charitable reading of the comment you replied to.

As you'll often hear from geneticists these days, one person's junk is another person's treasure.

There certainly was an attitude for a long period of time that our DNA was full of junk[0], but the field has since characterized much of what we once thought was junk (i.e. non-functional DNA) actually is just non-coding DNA[1] that serves one or more of a wide array of biological functions.

In many ways, you can't really blame scientists of the 70s for thinking that much of what we now know is ncDNA was inscrutable junk. In many ways, given the technology at the time, it was.

It's a super interesting area of study.

[0] https://pubmed.ncbi.nlm.nih.gov/5065367

[1] https://en.wikipedia.org/wiki/Non-coding_DNA

They're not calling it junk as part of an effort to down play it or to cause the rest of the field to deprecate or ignore it.

They're calling it that because the result is baffling. It's meant to be a call to action, not an affront to reason.

"Junk DNA" was a terrible name. But the article really should have mentioned something about how much of it actually codes for proteins (for both the fern and us).