In theory, publishers provide a real service, because self-publishing well is expensive (four, five digits easily). In theory, they should be offering access to people who couldn't afford what it costs to self-publish to the expected standard. In practice? The only people who can get in are people who have the connections and financial resources not to need the help. Whoops.

What we're learning about publishing (which we already knew, those of us who've been studying it) is that no one is good at selling books. Most self-publishers aren't, most traditional publishers aren't, and most PR firms are only good at taking and spending your money. We just don't have a good understanding of why individuals buy books (it changes) and there's a lot of evidence, sadly, that book sales are only loosely correlated to the quality of the writing (in the long term, quality matters more, but a book that dies in the short term won't have a long term).