Affected means that something was influenced or changed (e.g. the lyrics affected him).
Effected means that something was brought about or facilitated (e.g. she effected the proposed changes).
https://prowritingaid.com/affected-vs-effected
In the context of your sentence, the poor are affected (stuff was done to them) rather than effected (they brought about a change themselves). Affected is passive, effected is active.
IOW
I was affected by something.
I effected something (which may have affected you).
Unless I've got it all wrong in which case I'll humbly sing the sorry song whilst doing the sorry dance.

