The ASN and stuff is also operated by a US entity it seems like:

  ASHandle:       AS19281
  Street:         CleanerDNS Inc. dba Quad9
  Street:         1442A Walnut Street, Suite 501
  City:           Berkeley
  State/Prov:     CA
  Country:        US

They also have servers in the US, so that's yet another reason not to consider them "100% safe from US government intervention"

Also a quick search suggests that Switzerland has made Internet providers in-country block DNS results in the past.