Nobody is denying that it's effective. They're denying intelligence
A programming contest has a problem where given N < 10000, do something hard like come up with the number of primes less than N
You can come up with all sorts of algorithms that do intelligent things. But the most effective solution is to use metaprogramming to make a massive switch statement that contains all the answers
This is classic AI goalposts-moving.
OK, they can play chess, but that's not real AI - can they write poems? OK, they can write poems, but that's not real AI - can they compose music? OK, they can compose music, but that's not real AI - can they translate languages? OK, they can translate text, but can they do maths? OK, they can do maths, but can they solve a Millenium Prize? <-- we are here
Are they denying intelligence, or are they redefining it in such a way that only humans can be intelligent? Can you come up with a definition of intelligence that would apply to crows and ant colonies, which are obviously intelligent to some degree, but not the current generation of AI systems?