Meh. Nothing really new or insightful here. It's actually cartoonishly cliche advice at this point.
There are absolutely companies that have succeeded wildly without taking this approach, so it is not definitive by any means, in addition to not being novel.
On the other hand, there are plenty of great products that people are struggling to market effectively, for a number of reasons. Please, stop misleading people with the notion that marketing is easy if one simply "builds the right product".
When you're out there hustling and trying to solve tough sales and marketing problems, it's frustrating to keep seeing the same watered-down pablum on offer as advice.
It's even worse when the advice ends with "buy my product".