I have a similar but different thing I tell people: I think engineers should do a stint as a product manager. Spending time trying to solve problems on "the other side of the table" forces you to learn a lot about the business impact that different design, implementation, and prioritization decisions makes. Two years in Product made me a better engineer than the previous 5 years of cranking out features.

Thats not to say that a career product person will immediately be a good engineer. You need to be good at writing software. But if you get to a point in your career where you think your learning has kind of leveled out, go do a tour in product.