one other reason I can think of

Actually, there are a few other reasons to publish in “good” journals aside from internal university politicking, so for the sake of fairness, here’s one: they tend to have high-quality readerships, and you might not reach such organized readerships just by putting something up on the web.

For example, I’ll have a piece on literary criticism coming out within a few weeks in New Literary History. That will be largely a new readership for me, and all of those people would never have been likely to find something that I simply happened to post on a website.

So, what’s the lesson from cases like this? It’s that good journals will continue to retain value as a way of helping us to organize the world information glut. If you want to survey the state of the art in any given field, it’s a lot easier to go to a handful of leading journals than to search piecemeal through a variety of sources.

And I expect that phenomenon to continue in the next academic era. But what need not continue is the practice of articles being hidden behind subscriber-only firewalls, and articles being published 3-4 years after submission as too often happens. And I insist, the main reason people are willing to put up with these things is that their major “audience” under the current system has to be search committees and tenure and hiring committees. If you didn’t have to care about that (as I don’t care any longer) then your primary interests become speed of publication and size of readership.