I will agree, Backus' ideas have panned out in many ways. Not having read his lecture in quite a while I can't comment on whether or not, in 1977, he was overselling the idea at the time, especially as I'm not familiar with the state of the art in research at the time (having been born 5 years later, and CS concepts not being taught in chronological order).

Regardless, your original comment made two absurd claims:

1. Dijkstra attacked the paper that inspired Haskell and everything else that currently exists in FP. He tried to destroy it. [emphasis added]

Which is what my quote of Dijkstra's actual statements was meant to rebut. He did not try to destroy it. He criticized it, and some of his criticism may have been wrong then, and I'd say is wrong now (with greater understanding of the ideas Backus was presenting), but he did not try to destroy it.

2. He should be a footnote in history.

Another absurd position. Because of one response (and if you wanted to you can probably find a number of others) exaggerated beyond reason ("He tried to destroy it."), you want to dismiss some 50 years of work.

His hopes for functional programming machines seems like overselling his dream of abandoning von Neumann atleast. Arcane Lisp-machines was actually made as a comparison. I don't get the feeling Backus meant that a "FP system" should be an abstraction ontop of a von Neumann machine/language.

Based on what? What evidence is there that FP actually has any effect on a project?