While I agree that slavery is terrible and should be stopped, it’s a bit of a non sequitur to say there are more slaves than ever given there are so many more people than ever.
Now, if you’d like to talk about forced labor in developed nations, and the number of de facto slaves in specific countries where you wouldn’t expect to find any, that might be more relevant.
And yes, the vast majority of chocolate involves slavery in it’s growth and harvesting, which is also terrible.