That's almost certainly not what they did. When you see someone ranting about the 5G turning the coronavirus communist or whatever, that person didn't generally come up with that idea themselves; they were exposed to it online, either via friends, or via this.
Their algorithm is likely pushing extremist nonsense on people which it determines are vulnerable to believing it, which isn't the same as having an affinity for it. Obviously this isn't what they set out to do; they presumably set out to increase engagement, and if that happens to increase engagement, well...