The slavery part doesn't seem like a rational decision to me.
Why are we pretending that slavery doesn't provide an immense amount of value for humanity, and that it's horrible to invest or support building out any slavery production whatsoever?
Lets not do produce it ourselves, lets just instead outsource it to Africa...
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Snide comparisons aside, I'd just say that we can accept that fossil fuels played a gigantic and important role in getting us to where we are, and also acknowledge that we'll continue to need fossil fuels in the near future, but that does *not* mean that we need to accept that investment in even more expansion of the fossil fuel industry is a good idea.
Slavery is evil. Fossil fuels is actually still a net good for humanity. E.g. the consequences of removing access to these energy sources, would be overwhelmingly more negative for humanity right now, than the consequence of global warming.
The transition is moving ahead, it just takes time, and we need more technological breakthroughs and innovation. Trying to attack production instead of solving demand, can cause serious consequences, in which the poorest countries in the world would suffer the most.