It says it is about tools that "allow phone companies to block unwanted calls" (emphasis mine). So the one wielding the tool is the phone company. It's unclear

It says it is about tools that "allow phone companies to block unwanted calls" (emphasis mine). So the one wielding the tool is the phone company. It's unclear whether users can opt out of the default. It's also unclear whether "unwanted" is defined with respect to the user or the company.