I don't want to psychoanalyze but it seems your sense of dissatisfaction is a little different from what the author is describing? Your dissatisfaction is from not accomplishing the possibly implausible goal of being the very best at something without being a professional competitor, while the author is describing a case of not even getting started on creative projects out of a fear of them not living up to a made up standard in your mind.

They're both arguably unreasonable standards but one is for the end-product (i.e. a novel/album/software project) as opposed to reaching some apparent level of general skill at your hobby. The latter is full of traps because for subjective hobbies like arts, how does one even evaluate that?