Because a higher level of government recognizes that maintaining your neighbors’ lots exactly as they are in perpetuity is destructive to society as a whole.
Right, and it’s an adversarial process between that higher level of government, and local interests. What you’re suggesting is akin to asking people to forgoe the use of an attorney during criminal proceedings. The idea is that competing interests can find compromise where necessary, or at least that the adversarial nature of the process is preferable to alternatives.
Having apartment buildings along transit corridors in your neighborhood is really nothing like being convicted of a crime. The right to due process protects you from imprisonment, not neighborhood change.