The problem here is that what you are saying is correct, but incomplete and misleading.
When most men and women talk about qualities they look for in a companion, being 'smart' often comes up as one of the top 5 or 10 qualities.
The thing is, a lot of folks (particularly smart ones) thinks this means that intelligence, in itself, is sexy. It isn't. When people say they like a 'smart' companion, what they really mean is 'smart enough,' or 'not stupid.' It's a low threshold as almost everybody meets that criteria.
That's not to say so much that intelligence, in itself, is sexually appealing. It is to say a pronounced lack of intelligence is unappealing in a long term romantic companion.
Actually, a very intelligent person who is abrasive, rude, or otherwise a poor companion will likely be rejected in time, in favor of a more appealing companion, even if they are less intelligent. So long as they aren't dumb, they will satisfy the very misunderstood 'intelligence' criteria.
When it comes to men, if all they knew about a woman they could meet was that she was very smart, it would be neither a plus nor a minus. He wouldn't be particularly excited to meet her, or particularly disinterested either.
When it comes to women, if all they knew about a man they could meet was that he was very smart, it would be a slight plus, and in most cases not a minus. She might be slightly more interested in meeting him, now would she be particularly disinterested either.
You are correct. You have to have other qualities as well.