Most ordinary people will laugh in your face if you try to sell them on chattel slavery being the same as wage labor in poor conditions. It doesn't matter in the slightest how correct you think that comparison is -- it's not going to get you very far, and it will cause some people to simply tune you out. You're setting yourself up for failure for no reason at all.

It's much easier to sell people on how terrible Batista-era Cuba was. Pick your struggle sessions.