Is that really true though? The right to distribute a work isn't tied to a specific medium. A contract between an author and a publisher can divide up the right by medium if it wishes but an unspecfied "right to publish" would include the web already. Seem like you'd need to read the specific contract in question and have a good knowledge of the relevant precedents to draw a conclusion here.
Even if you're correct, works after 1923 would not enter the public domain, because the author never relinquished their exclusive right to web publication.
Of course even for a public domain work, there's nothing to prevent a publisher from charging for it.
Yes, it really is. The chairman of the Royal Dutch Library paid a pretty expensive lawyer for a reasonably long amount of time to get this figured out once and for all, the rights did not automatically transfer from the author to the publisher so technically they still lie with the author or in applicable cases with their estate.
That's not the public domain though - the authors still own the work, the public has no right to it. Do you have a citation for the "figured out once and for all" information, I can't seem to find anything?
Even if you're correct, works after 1923 would not enter the public domain, because the author never relinquished their exclusive right to web publication.
Of course even for a public domain work, there's nothing to prevent a publisher from charging for it.