"
High prestige journals offer value to both authors and readers."
This is a very odd situation that I suspect isn't really amenable to normal economic analysis, at least outside of very simplistic models.
The value that journals offer is, over the medium term, due to the editorial staff and the authors that submit articles. Remove those two, and the journal will cease to be "high prestige" and will likely fold. In the short term, however, the value is in the journal's name: you could replace the editors of Lancet with a crop of corn husks and it would still be "high prestige" for quite a while---at least until the third or fourth major screw-up. (Losing the authors is harder, but hold that thought for another paragraph.)
On the other hand, over the long term, the value lies entirely in the readers. No major academic is going to waste their professional capital on a journal that isn't read by their colleagues, and ultimately, an academic's articles need to be read, not just published, for them to advance more than locally.
In the same way, new journals have issues: In the short term, it's hard to get over the name recognition hump; in the medium term, they have to have consistently good editors and authors to attract more than momentary attention. But once they have attracted a readership, they have an inertia that makes other factors less important.
A couple of examples:
* Anyone heard from Software: Practice and Experience lately? It was one of my favorite journals, and was being edited by Douglas Comer the last time I interacted with it. But I haven't seen an issue in more than a decade, mostly because it is (was?) hideously expensive, and haven't seen any references to it, either.
* How about PLOS? Seems to be high prestige now, judging by the number of references I hear on the Science and Nature podcasts.
My personal suspicion is that a better analogy for Elsevier and company is the mining business: extracting as much wealth as possible from academic journals, as cheaply as possible, before the ore runs out and the town dries up and blows away.