I totally appreciate your perspective, David, and I'm guessing that - for you - product and engineering functions are highly aligned. What a great place to be!
There's a different scenario that I've seen time and time again at new companies and old where there is a dysfunctional relationship between product and engineering.
In these cases, there is an imbalance in the leadership between the two groups, and engineering loses its voice.
The conversation moves from "what's the impact of addressing this concern now versus later", to "how quickly can these new features be delivered".
It gets even worse when the size of the product organization is relatively large compared to the size of engineering and demand can outstrip supply by an order of magnitude or more. It's even worse when the product team uses irrational approaches to feature prioritization rather than empirical, data-driven methods.
Over time, the compromises that are not addressed compound just like regular debt and the compromises that software development team make get progressively worse. Have you seen cases where developers are too afraid to touch a piece of cold in a legacy app and so layer something new on top? It's like that.