Second, relevance and applicability is depending on context. On the context of this discussion, about practical programming in the trenches, what Dijkstra said is irrelevant.
For starters, he was talking about computer science.
Programmers in the trenches (what the thread is discussing) don't do computer science. They merely apply stuff developed by computer scientists (but also by non-scientific practioners in the field), in informal (and often haphazard) manner, to solve business problems (often the same problems again and again, which is something totally beneath a scientist).
So, yes, something Dijkstra had said can still be wrong, regardless of his achievements. And it can also far more easily be irrelevant, as this just needs his saying to be unrelated to the discussion.
