Genome signatures.
Cloned scams, tagged.

Grouped by one shared technical trait. That is a lead, not a verdict: shared hosting, common templates and reused libraries also tie together large numbers of unrelated sites. Check each domain on its own report before drawing a conclusion about it.

Technical traits shared across scam sites

Each signature is one trait found on more than one domain: a page structure, a site icon hash, a reused tracking account. Every one lists the domains carrying it.