I think finding fault with this kind of opinion is a symptom of the modern concept of "taking offence". Ie nobody can express an opinion without also showing that they respect others' opinions. But that's not right. We don't have to respect each others' opinions if we think they are wrong. What we must do in a free society is respect their right to have, and express, a different opinion.
Dijkstra clearly thinks that teaching BASIC is damaging people's brains so he says that loudly and clearly with a touch of humour. Should he water it down to avoid offending people that like BASIC?