In this case since the algorithm doesn’t (obviously) have nazi advertising to show you, it shows what it has instead.
So the companies clearly don't want to then become associated with nazi-posting, because then it might have the connotation of being Nazi adjacent because they didn't say anything. That's basically the definition of tacit support.
How is it so hard to understand that normal people don't want to associate or even be implied to associate with Nazis or their content? Pulling out of twatter is the only sure fire way of keeping their ads away from the Nazi base that's made it's home on twatter with the express approval of its idiot founder.