HN is way too central for shared sentiment in the tech world for these companies not to do some amount of astroturfing. AI companies have shown at every single turn that they act out of self-interest and greed, not of moral principles. So it isn't surprising, even if it is still sad, to see those who are commanding the most capital in human history act with such callousness.
I think the appropriate course of response is to stop adding to public spaces on the internet. No doubt painful for those of us who have so benefitted from the freely shared thoughts of others. But if well-funded bullies are going come in, steal everything, ruin the commons, and then say "this is the new normal, deal with it", there isn't much the rest of us can do other than stop feeding them.