For any local program, I can block its access to the network and still use it. For a program whose functionality requires internet access, I can either inspect

For any local program, I can block its access to the network and still use it. For a program whose functionality requires internet access, I can either inspect every outgoing packet for exfiltrated data, or I can choose to trust some programs to be non-malicious based on their reputation. That trust is incredibly fragile, and unannounced spying/telemetry breaks it.