Electronic books, my opinion.
This opinion comes from 20 years of being published and staying published in print.
An electronic book delivered to your computer or E-reader is a FORMAT. It’s no different in its content than a book delivered in print. Note my word use. E book is a format. NOT a new type of book. Some of my books are available for E format, some not. Print publishers think the same way. Check out anything on the subject by Jen Enderlin, publisher of St Martin’s Press. Anyone can upload a file. It does NOT make you an instant writer.
The Author’s Guild & Mystery Writers of America don’t allow self published to be members and in both instances, you have to prove it by submitting two books for a membership. (Or a copy of the contract pages, I can’t recall)
You are not published unless you have sold the work to a publisher who pays you an advance and then edits and prints it. (or E formats it) I wonder how so many miss this detail. It is the definition of a published writer. I have never laid out one penny to see my books in print. Not one.
A financial investment of any kind from you makes it Vanity press. I didn’t make the definition, or the standard. Previously in RWA, that was a huge no-no. Now, anyone can publish what resembles a book and call themselves a writer. To me, after the hard work it took to get published, is insulting. It’s also the reason I did not renew my RWA membership after 22 years.
Electronic books are a format. Imo, there is no real question. You were either paid for your words or not.