Is it permissible for a needy person who cannot afford a home except by renting due to poverty to blame the ruler for not caring for the housing of the poor, and is that considered backbiting?

Gheebah (backbiting) is mentioning your brother with what he dislikes. So, if you speak about the ruler with what he dislikes, such as his lack of concern for the poor, then this is gheebah. Two cases are excluded from this:

1. Complaining to an authority that can remove the injustice.

2. If the ruler openly commits فسق (disobedience/immorality) or injustice, then it is permissible to mention him only with what he openly commits.