Did you even read the linked thread, of a person apparently actually working with homeless people? It explicitly mentions that email is the preferred method of communication for many of them, for reasons also mentioned in the thread.

> The homeless have challenges, no doubt, but that does not imply google worrying about 2FA for the homeless is the best way to solve those challenges.

You seem to be under the impression that improvements to the condition of people's lives are only ethically acceptable if they happen ordered strictly by descending impact. In my experience, that's not realistic.