Apple added hooks a while back so that 3rd party apps can interject into the call process, and I've been using https://hiya.com https://hiya.com to do that and

Apple added hooks a while back so that 3rd party apps can interject into the call process, and I've been using https://hiya.com https://hiya.com to do that and block scam calls. I have it set to disregard suspected scam/fraud calls, so they never ring my phone.