Building a brand is a long, ongoing process. You need to have a self-consistent set of values, and those values need to show through in your products. (I mean, there is more to having a brand, but without those consistent values, the other stuff doesn't matter.)
I find it really ironic that this article comes from an "ad man" and a "principle of a strategic marketing firm" because he knows very little about marketing.
Also, building a brand and marketing sound similar but are very different. In personal terms, you, as a brand would be 'what others to think of you', and marketing is 'what you say about yourself / present yourself'. Sales is how you 'turn an audience into followers'. Since sales = marketing + brand, in the analogy above 'audience to followers' = 'what you say about yoursef' + 'what people think of you').
You cannot argue against the function of marketing in a waterfall framework. Then praise the lean methodology. For this to be apples to apples, you should compare waterfall to lean, and marketing to no marketing (an extreme form of which would be to have no web presence).
The way I see marketing is things that need to be done but a hacker might not enjoy doing.