The book example is not very helpful for a few reasons.
Firstly, the authors of books do get paid—writing books is not a pure tax imposed by academia.
Secondly, books are not typically at the frontier of scientific knowledge (these days). They're interesting and helpful, but accessing them is not a necessity for keeping up to date. Put simply, books do not have a monopoly on knowledge.
Finally, and most importantly, books are not funded by the public. Research is. If the public is paying for something, they should have access to it.
Firstly, the authors of books do get paid—writing books is not a pure tax imposed by academia.
Secondly, books are not typically at the frontier of scientific knowledge (these days). They're interesting and helpful, but accessing them is not a necessity for keeping up to date. Put simply, books do not have a monopoly on knowledge.
Finally, and most importantly, books are not funded by the public. Research is. If the public is paying for something, they should have access to it.