The simplest, surest and least blood-letting way to destroy the criminal TPLF is to recognize the nationalities within the "Tigray" construct.
Not only recognize but support their right to self-determination without reserve. And there is a precedent for this. The Amhara region!
Give them their special zone, give them their own government, let them defend their territory.
Imagine if Abiy was to form the Tembien-Abergele special zone, right now! The criminal terrorists would be flushed out with very little effort.
I am saying think with fore-knowledge that this is INEVITABLE if TPLF continues with its insurgency. WHY then wait?