One thing is that those aspects map to quite real needs, and the book does provide a set of reasonable metaphors to talk about those needs between partners in a way that gets the point across where previous attempts didn't succeed. It's genuinely hard for many people to define and communicate their own feelings and expectations, and even more so for someone else's feelings and expectations, complicated by the natural tendency to presume that other's preferences work similarly to yours, so a framework that helps this communication is really useful in those cases where relationship problems involve a misunderstanding about those expectations; which is not all relationship problems but certainly a meaningful part of them.
In the examples you provide, I would say that it's exactly the right lens to apply to those situations - it's imperative for both parties to understand that those are the factors that matter instead of trying to work out a relationship around them, ignoring those core issues; and this lens allows to understand/specify/communicate it better.
Like, if someone does derive validation from your sexual interest, then that's a quite important thing to understand for the partner (even if for them personally the concept of needing such validation is a bit alien, because their self-worth is filled differently), because that's not going to change easily and is going to be a big factor in making the relationship work. And if someone is materialistic, pretending otherwise won't be helpful and neither will trying to change someone's values, that generally takes huge time and effort and/or crisis events. Of course, obtaining a proper understanding may also mean understanding that the relationship should not continue, but for such relationships that's also a beneficial result.
There may be more effective ways of facilitating this communication and common understanding of the partner's inner needs, e.g. perhaps couple's therapy can do it faster, but that's a quite expensive process and a simplified set of metaphors can be a cheap and useful approach ("A change in perspective is worth 80 IQ points") if there's sufficient material to ensure that both partners, likely coming from very different perspectives given that they have this communications problem, get a common understanding of how they understand them.