I thought this was worth putting into a chart. Assuming an average author life of 75 years, this is what the extension of maximum copyright terms looks like:
Basically, it's well approximated as an exponential curve, or maybe a logistic curve (aka S-curve). Unless there's a serious change in the accepted perspective of copyrights, it's not at all unreasonable to assume that within our lifetimes, copyrights may be extended to last effectively forever.
Mary Bono: "Actually, Sonny wanted the term of copyright protection to last forever. I am informed by staff that such a change would violate the Constitution. ... As you know, there is also [then-MPAA president] Jack Valenti's proposal for term to last forever less one day. Perhaps the Committee may look at that next Congress."
That's pretty unrealistic. You seem to be assuming authors who write as infants. Even the most precocious authors usually wait at least until they learn to speak and read before they start publishing.
https://skitch.com/swombat/fbhmf/maximum-copyright-terms-us
Basically, it's well approximated as an exponential curve, or maybe a logistic curve (aka S-curve). Unless there's a serious change in the accepted perspective of copyrights, it's not at all unreasonable to assume that within our lifetimes, copyrights may be extended to last effectively forever.
Tragic.