Okay, this got a bit longer than I intended so I split it up into different points:
1) But society has already been fully restructured into something completely different. It's foolish to believe that we can get from one local optimum to a higher point without interruption if the only reason we're at the local optimum is that the previous one was violently interrupted in the first place. It's also foolish to believe that history is a linear trajectory towards something good or better, though this is indeed what most schools tend to teach because it avoids the difficult questions.
2) The status quo is unstable and will inevitably lead to accelerationism. You can not overthrow injustice without violence as those benefiting from the injustice have no interest in giving up those benefits without violence. Maintaining the status quo if it is unjust is in itself a violent act. The status quo isn't stable, most of us are just sufficiently detached from its injustices that it feels stable and safe to us.
3) That political action is violent doesn't mean it has to manifest as a revolution or civil war. We like to glamorize the suffragette movement as a non-violent political struggle that mostly consisted of women holding up signs but suffragettes were literally performing actions we would today label as terrorism. We like to appeal to MLK as the voice of reason and imagine that he ended racism by talking in a kind voice but his protests were literally portrayed as riots at the time no differently from how we portrayed the 2020 BLM protests today. The US itself was created in a violent revolution and had to fight a war against its own people to prevent a secession only a century later. Not every instance of social progress requires a complete overthrow of the entire system but the more intrinsic an injustice is to a system, the more violent will those benefitting from it defend it against anyone trying to change it and the more violence will be necessary to overcome this resistance.
4) Revolutions and civil wars are often not caused by a desire for things to better but as a reaction to governments actively making things worse. Cambodia is actually a great example in that the sharp turn to the ultra-right was a direct response to incremental progressivism that preceded it and this in turn necessitated a violent revolution because there was no way to recover from this shift without it. Incrementalism had not only failed but was violently halted and reversed by those benefitting from the existing power structures. By trying to undo the incremental changes they drove progressives into the arms of the Khmer Rouge who had positioned themselves as the opposition and were now seen as justified in overthrowing the system as a whole.
5) The question isn't whether we should oppose charity, the question is whether charity can solve problems created by the power structure that enables a tiny minority to engage in charity in the first place. And the answer is clearly no because it hasn't and there's no reason to believe it will. Charity is a form of wealth redistribution but it is extremely inefficient in more ways than just the obvious bureaucracy involved in maintaining charity organizations to develop and implement social works projects to actually help people in defined and limited ways. That's just food stamps with extra steps. The problem is that charity is itself replicating the top-down hierarchical dynamic by forcing "interest groups" to compete for scraps: whether the money goes to breast cancer research, education for people living in poor areas, treatment of AIDS patients, or exterminating the mosquitos that spread Malaria is entirely up to the market, i.e. the few extremely wealthy shopping for a philanthropic cause to support while saving taxes, indirectly transferring money to business partners, or legally bribing officials.
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I don't oppose harm reduction in itself. Voting for the less bad political party is probably better than allowing the more bad political party to win. Billionaires funding technological innovation is probably better than billionaires spending the same money on union busting or propping up totalitarian governments. But the question isn't whether we want the revolution or not, the question is when the revolution will come and who will win. And how we prepare for that.