There are so many simple solutions, just like phone privacy is fixable (firewall your phone) I just don't think anyone wants to fix it. Why can't apple let us

There are so many simple solutions, just like phone privacy is fixable (firewall your phone) I just don't think anyone wants to fix it. Why can't apple let us send "spam risk" to voicemail? Like adding extensions, possibly with passwords to your phone line. It would be good to give an extension or password to friends, or one for each business, which can be automated to input with a pause after answering, and it gets through (or further) if possible. we should have phone rules just like mail rules.