Yes, but I don't think you're considering the significant direct cost to the owner of SOUQ.COM for DNS queries. If all of a sudden I get millions of extra DNS queries for my domain because Signal is using it to front their traffic to CloudFront, I might get a huge DNS bill.

Should any government coerce me into paying a large DNS bill just to sponsor freedom of speech? Even if it is a noble cause, we shouldn't coerce innocent 3rd parties into doing this.