Contrast the Alan Kay quote that says you should find the most complex construct you possibly need, and build everything in terms of it. (again my google fu is weak)
If Alan Kay's the person to credit for OOP, I guess that doesn't surprise me. ^_^ A simple basis of complicated things is just fine. For instance, not all our lambdas actually need to be closures, but that doesn't stop us from reasoning about them as closures for the sake of reducing the number of concepts we're juggling.
The problem comes around when people forget how arbitrary any particular complicated basis is. XD I'm looking at you, "Arc needs OOP" threads.
So maybe the Dijkstra and Kay quotes are compatible, in a sense. Kay can be encouraging people to find appropriate foundations from which to implement concepts, and Dijkstra can be encouraging people to perceive the concept itself rather than taking its implementation for granted.
I guess I can't really say that without knowing more of the context of what Dijkstra and Kay believed. Still, a quote more opposite to Dijkstra's might be this one:
Beyond the primitive operators, which by definition can't be written in the language, the whole of the Arc spec will be written in Arc. As Abelson and Sussman say, programs must be written for people to read, and only incidentally for machines to execute. So if a language is any good, source code ought to be a better way to convey ideas than English prose.
- Paul Graham
I think it's similar to foundational math and philosophy. An implementation (model) of a system in terms of another system can admit implementation-specific proofs of things that are false in other implementations. Just because one model or formalization has been found doesn't make it uninteresting to continue considering the motivating informal system on its own merit.