I honestly think that this is filled with an undue sense of inferiority.
With the first example on first aid;
Consider the bystander effect. It is incredibly unlikely that someone will actually take initiative to help -- at most, someone might just call an ambulance. Simply taking initiative, even if it is limited only to giving requests for help, is a huge positive
I also think that the author overestimates how many people are good at first aid, and even more the number of people who are good at first aid and take initiative
As for the second example;
Starting a project does NOT prevent others from starting similar projects. You will always find several businesses / projects on the same topic.
You could argue that no one can use the resources you've "wasted" but someone would have eventually used it, and that person could be a psychopath.
Besides, what makes YOU think that you are not one of the best people for the project? Even if you are not the best in a global sense, you can still be the best one locally. (e.g. you are not a Nobel prize winning economist, but you are the most qualified applicant for the project)
Lastly, the fact that you are willing to consider this advice means that you are probably better than most for it. Telling people not to be narcissists nor to be abusive does not work on narcissists and abusers, it does however affect everyone else