The explanatory value of mythological tropes is of a different nature than that of scientific facts. Humans construct internal mythological models, whatever the source material. In fact most of those who think they are working from a scientific model of the world have just assembled metaphors afforded by scientific facts into a mythology.
The specific Daoist imagery around yin and yang embodies specific messages that are of value, among them: 1) Weakness and incompetence are largely illusory, and apparently weak behavior is often adaptive leverage that simply works more slowly and involves a broader range of action. 2) All strength involves some underlying weakness and actually derives its ability to persist from the flexibility imparted by that weakness. 3) But without looking within the weakness for the underlying strength and within the strength for the underlying weakness one may often be legitimately weak or unexpectedly fragile.
You can get the same message from metallurgy, if you want, via a different kind of metaphor. But that is just constructing mythology out of science: Annealing gives you a basis for a metaphor. It does not actually say that, or mean it, it just makes the impression stick. And the fact this can be embedded in a more modernist framework does not mean those messages are not reasonably communicated by this directly mythological trope.
It does not matter which thing you take as a metaphor, this particular message is so broad as to be buried within any situation that involves durability or power. So you can look at the sun as a physical object, and find the metaphor reflected that way, or you can look at the Classical Chinese interpretation of the sun through human experience that appears in the framings of the Yi Jing. They both net the same insight, if you just take up the framing. And you can also look at any other star. The meaning might be easier to capture if that star happens to have a planet around it with life on it. But that is not truly necessary. For that matter, you can look at your own exercise regiment, or at the fish in a koi pond, and find the same message.
From a Jungian perspective, a lot of our shared psychology evidences archetypes like this. In the West, the elements, the layering of worlds, the sequence of aspects, etc. from Alchemy, Astrology and Kabbalah are equally not nonsense. They don't realistically predict anything. They are not physical facts, or even 'spiritual truths'. But they encode messages that are easily shared, and that can be used easily to greater psychological effect than more correct facts.
When a computer scientist takes up a pattern like Model-View-Controler, 90% of the intuition here is captured in the Astrological notion of the three aspects: that the durable aspect of something (the Model, its Fixed Nature), the representation of it (the View, its Mutable Nature), and the mechanism of control it affords (the Controller, its Cardinal Nature) are best understood separately, even though they are different perspectives on the same interaction. By not mixing them, they will be easier to communicate. This is not really 'true' in any deep way, but it is conducive to human psychology.
And when the Japanese and Korean car industries decide to adopt a hyper-egalitarian, just-in-time approach that disowns specialist knowledge and explicit strategy and empowers the random worker on the assembly line, it is invoking an acknowledgement of yin, and the understanding that human mastery of machines needs to employ both forms of power.
