We can talk about wages and employment rates, and race all day long, but those are just details. It's human greed in the end, and our inability to love others like we love ourselves.
While I don't necessarily agree with everything the poster is saying--implying that someone is only allowed to discuss topics in which they have a readily available solution would likely ruin most discussion on the internet and it would certainly put a damper on scientific work the world over.
But whether the "enlightenment project" benefits from simply making complaints is a valid question. I still think the answer is no, or at least that if you're going to make a complaint, your position is improved by proposing a solution for discussion. I concede that it might be possible to make an effective and evidence-based counterargument, but are there meaningful social movements which have been based solely on complaining about stuff with no action platform?