I think am qualified to answer this question because I from Tigrai. Am not supporter of TPLF I actually voted for Arena(opposition party in Tigrai) last election but still am not supporter of Arena either. TPLF was dictator for sure but they have done a lot Economically for this country weather you believe it or don't and tried to govern the country with system that they think is best for the country Federalism. So when I come to your question why people in Tigrai still support him first when TPLF was fighting against Derg almost every family in Tigrai have lost someone their child, husbad, wife ... Second the most important one is the current government in power wants to dismiss everything TPLF has ever done and accuse every thing on TPLF. The thing is if every EPRDF was committing a crime they deserve to be thrown to jail but not only TPLF(And I think this is the main reason). And for people who say they are brain washed bla bla no this is a choice I was not supporter of TPLF but now I don't want TPLF to go down at least until Ethiopia is fully peaceful.