Ineffective seems harsh.
If humans were as bad as LLMs at basic math and logic, we would consider them developmentally challenged. Yet this constant insistence that humans are categorically worse than, or at best no better than, LLMs persists. It's a weird, almost religious belief in the superiority of the machine even in spite of obvious evidence to the contrary.
Clearly, humans also need training in these things and almost no one figures out how to do basic things like long division by themselves. Some people sometimes figure things out, and more importantly, they do so by building on what came before.
The difference between humans and LLMs is that even after being trained and given access to near everything that came before, LLMs are terrible at this stuff.