I'm so sick of the trope of the happy sexless marriage. It's unhealthy and it's the cause of a lot of unhappy marriages and delusions out there. This article doesn't address the trope and instead reinforces it.
I have known couples who need sex every day, and I've known couples who have rarely have sex. Both happy. Mixed it up and swapped them around? Deep unhappiness.
Stop projecting your preferences onto every other human: the amount of sex you prefer in a relationship is unlikely to be a perfect match for everybody. You especially need to be wary that if you are inclined to have a lot of sex and your partner is not, you may unwittingly be forcing them into something they are not comfortable with, and as a result making them deeply unhappy.
It's not a trope. It's just basic human understanding.
The truth is that a marriage needs as much sex as it needs, no more, no less. There are people who are perfectly happy in sexless marriages, and people who are miserable in marriages where sex isn't a problem.
The most important ingredients for a happy marriage are two people who are well sorted ou. Everything else is negotiable.
I think it would have been great for her to at least talk about their sexual frequency and how agreement of frequency is important, otherwise that lack of passion undermines everything.
TL;DW: Just like sex doesn't have to be about penetration, foreplay isn't just about touching or dirty talk.
Intimacy is about sensuality and closeness. Those don't have to be anything to do with sex. For example, it's possible to experience intimacy in a completely non-sexual setting, such as a honest conversation about death. Intimacy is about the feeling of closeness to someone, not about what that closeness results in.
I think aside from skewed attitudes towards sexuality the problem with the concept of intimacy in particular is that the word is often used as a euphemism for sex -- "being intimate" usually refers to having (had) sexual intercourse.
And the word sexy is already popular in many non-explicitly-sexual contexts. Like "intelligence is sexy", "sexy car", "sexy clothes". I'm pretty sure I've described code solutions as sexy a number of times. But unless you're into mechaphilia sexy cars are not sexually attractive.
For example, men seem to be most attracted to women in their 20ties. While I acknowledge the (evolutionary) reasons for that, I also think it sucks, sometimes to the point of disavowing sex just to spite nature.
It is of course possible to pursue young women even as an older man, but there really is a tradeoff between attraction, dignity and sheer waste of effort.