But they said "has yet to content with"

Unless you do in fact mean that every single system of governance, including things before slavery that are hard to conceptualize under one framework, extreme state control (whether you believe NK, USSR are actually socialist or not), etc. etc.

I'm not making a pro-capitalist argument, merely the point that

And ignoring the issue of slavery historically-- "has yet to content with"-- does seem a bit of a deliberate sidestep. Of course capitalism will be the primary consumer of slave labour, but slavery, absolute poverty, etc are lower and falling. Further, modern slavery is completely terrible but less severe than chattel slavery, or slavery that came before that.

But again, my argument was never that capitalism is better than anything else, merely that it isn't the most evil thing. Genocide might be. Or something completely different.

Sure! However AI itself also has AI specific concerns that are orthogonal to the socio-economic system under which we live in or they are created. Robert Miles on YouTube is a great entertaining and educational source for this

But it seems that the AI alignment issue is also a big concern, too. In either case-- capitalists using AI for SUPER CAPITALISM (i.e. can do all normal capitalism things but faster, more effectively) and so the issue solely being in intent and motive, or capitalists incorrectly specifying outcomes (cutting corners to make profit) leading to misaligned AI that does really bad things, your arguments against capitalism only strengthen the concerns we have with AI

Because of how foreign AI can be. In the space of all human brains and worldviews, there is insane variation. But beyond this, in the space of all minds evolution can create, and all minds that could ever exist, a random, generally intelligent and capable AI could be the paradigmatic example of completely banal evil as it kills us all.

Is capitalism the most evil thing humanity has dealt with? More than feudalism, slavery, etc?

Further, AI isn't really imaginary-- at worst the author is trying to pre-empt and avoid an issue that is less likely to come to pass