All involve allegedly self-represented plaintiffs, yet they have similar snippets of legalese that suggest a common organization behind them. (A few others, having a slightly different profile, involve actual lawyers.)

All the ostensible defendants ostensibly agreed to injunctions being issued against them, which often leads to a very quick court order (in some cases, less than a week).

Of these 25-odd cases, 15 give the addresses of the defendants -- but a private investigator (Giles Miller of Lynx Insights and Investigations) couldn't find a single one of the ostensible defendants at the ostensible address.

schwit1 quotes a report written by Eugene Volokh via Washington Post:

Now, you might ask, what's the point of suing a fake defendant (to the extent that some of these defendants are indeed fake)? How can anyone get any real money from a fake defendant? How can anyone order a fake defendant to obey a real injunction? The answer is that Google and various other Internet platforms have a policy: They won't take down material (or, in Google's case, remove it from Google indexes) just because someone says it's defamatory. Understandable -- why would these companies want to adjudicate such factual disputes? But if they see a court order that declares that some material is defamatory, they tend to take down or deindex the material, relying on the court's decision. Yet the trouble is that these Internet platforms can't really know if the injunction was issued against the actual author of the supposed defamation -- or against a real person at all.