Sure, but if you broaden the word "intelligent" to include the behavior of mycelium you probably need a different word for the quality only shared by vertebrates and cephalopods with more complex brains and internal representations of the world. Then somebody is going to use that word for fungus too and on and on. The key disagreement is the comparison in quality being measured between humans and to a lesser degree many animals and the degree of that quality had by fungi. The article is using a word in such a way that less familiar people make false associations between fungi and animals with brains. Like using the same word for a hammer and an industrial assembly robot. Ok sure, both "tools", but an article in a popular science magazine is trying to bring things close together which really are not, mostly because that kind of idea appeals to a kind of person who doesn't have very much knowledge. It's not harmful to debate the word intelligence, it probably is to go around using the word with a common understanding and broaden its meaning to make an appealing but misleading point.

So you are saying that portraying the levels of alive vs. intelligent as too similar can be detrimental and is used as a cheap tactic to appeal to a certain kind of lax thinking. I agree. I also think people can be too quick to write off systems or things they consider unintelligent. When we think it is just a “dumb” fungi or whatever else, it takes us longer to recognize true complexity and intelligence in a different form than we are used to. So I personally lean more into defending looser definitions of intelligence and aliveness because I think there’s a lot more to some of these systems we may not have the perspective for yet. I see the argument for a tighter definition too.