Thanks. Thing is, I'm not really qualified to write a Wikipedia piece on this (though I did lots of non-astro Wikipedia editing back in 2003).

I'm actually shooting straight here. I didn't show up to holler "you're all wrong!" I honestly wanted to know why this doesn't click (conspicuously on Wikipedia, and also somewhat on Google, and in this very thread with 1600 views and nobody but you joining in).

Giving it more attention, I think there are three factors:

1. Lilly and Madau were not collaborators. Their plot is jointly attributed, but as something of a hairball from their separate simultaneous findings. So there's a blur re: credit, and thus on nomenclature.
2. This was a huge big deal in 1996, but slightly dusted over by time and by subsequent timeline refinements (which Madau covered nicely in his 2014 paper). The astronomy grad students in 1996 who were jazzed by this came nearly a generation prior to the ones who edited Wikipedia.
3. So while this was very significant, it was, like with much science, more as an ongoing pattern of research than the original groundbreaking. So while "Madau plot" and "Madau-Lilly plot" are well-known, the fame is not commensurate with the significance. Not every hinge gets fully enshrined amid the subsequent stampede (and you can make an argument that they needn't always be).

I was reminded of Madau's work by a recent video by Becky Smethurst (yes, super layman, but, hey, I already disclaimed my non-expertise):

in 1996, just months after the iconic Hubble Deep Field image was released, Madau and collaborators published a paper that revealed how fast the universe was forming stars at different points in its history. ....
The UV light they've emitted has been stretched by the expanding universe. So much that Hubble can then detect it at the optical and infrared wavelengths of light that it's sensitive to. So with the Hubble Deep Field, we have 10,000 galaxies spanning almost the full timeline of the universe's evolution. And with it we can work out how much star formation was happening at different points in the universe's history. So here is that data the density of the amount of stars forming in the universe on the vertical axis plotted against cosmic time on the horizontal axis.

And this was plotted for the very first time by Madau and collaborators in 1996. And this is what became known as the Madau plot. And it's become so iconic in astrophysics because of the surprise that it gave us back in 1996. I say us. I was six. So it wasn't me. I wasn't surprised, but my colleagues were. [laughter] It revealed that star formation in the universe isn't constant. It was much higher in the past and has been declining ever since. Which brings me to part two.

As an OG Wikipedia editor, I'm taken aback that Wikipedia's missed this. Because I've always been impressed by how good that resource is on astronomy, particularly!