You are absolutely correct. The fact that this statement is made by a website holding itself out as an educational source is very disappointing.
Ultralight vehicles meeting these requirements (weight, single seater, etc.) are subject to NO airworthiness regulation by the FAA at all. So the FAA is making no statement on whether they are safe or easy to fly.
What these regulations mean is it is not a crime to fly something meeting these requirements (even if it was assembled by your crazy neighbor in their shed). That doesn't mean anyone would think it is a good idea, let alone the FAA.
In my corner of the world/philanthropy discussion, I'd consider GiveWell one of the most well-known organizations and with a reputation of high quality, thorough research. In terms of charity evaluators who focus on the impact per dollar spent, I'd have a hard time thinking of anyone comparable.
Regarding what type of programs GiveWell currently recommends, they do evaluate a wide range of types of programs. For instance, here is a page on their website summarizing some of their work on education: https://www.givewell.org/international/technical/programs/ed.... However, with the facts as they exist in the world today, their analysis is that for a given amount of funding, more good can be done with certain specific health interventions.
Ultralight vehicles meeting these requirements (weight, single seater, etc.) are subject to NO airworthiness regulation by the FAA at all. So the FAA is making no statement on whether they are safe or easy to fly.
What these regulations mean is it is not a crime to fly something meeting these requirements (even if it was assembled by your crazy neighbor in their shed). That doesn't mean anyone would think it is a good idea, let alone the FAA.