Is branding not important for ebook writers etc.?

[David]

I was talking to a web designer recently and he told me that there is no point in trying to become "known" if you are selling "fitness" ebooks, "how to" ebooks, or any category of ebook that is common because nobody remembers the names of the guy behind them unless they are very successful and in a very short amount of time people will copy it and put it up on fiver, their blogs and other.

Is this true, if not what are the fundamental branding methods that need to be utilised?

Thanks.