For mass market products, maybe. What about photoshop? music production software? what if your customers are developers and your product is a software library?

In many cases there is an inherent complexity to a product, and it warrants some learning curve. Removing the need for documentation often removes power and depth.

Funnily, now that many products are like this, the opposite trend is surfacing, and in some niches you have customers who love reading manuals. It becomes part of the user experience.