bu but NeVeR bEen CoLoNizEd Saar 🫡Ethiopia borders were made by colonialists same as Somalia Kenya and rest of east Africa
I'd say this is mostly right but what your missing is the actual reason why Ethiopia isn't more developed.All the various post WW2 regimes Ethiopia had were autocratic messes, more concerned with maintaining their power than actually developing the nation. This in spite of the fact that Ethiopia was being given heavy support from the west in the form of billions in aid. Its really telling how bad things were that Ethiopians were willing to overthrow their 700+ year old ruling dynasty so they can finally attempt some form of modernization and economic reforms that Haile Selassie largely neglected. But that ended up largely being a pipe dream seeing how badly the Derg messed things up and so the post Cold War governments of Zenawi and Abiy tried to pick up the pieces with mixed results.
But really I think the heart of the problem really come down to a lack of cohesive identity and unity among Ethiopians. There are two types of Ethiopian identities: you have the original "real" one that has its roots within the Christian Habesha highlands, and you have the modern Ethiopian identity which consists of a vague pastiche of ethnicities that share little in common with each other. The former identity historically was the main driver of Ethiopia and consisted of ethnicities (Amhara, Tigrayan, Gurage ect) that largely shared similar cultures, politics, and geography while the former identity consist of newly conquered groups. Now large diverse countries can be functional as seen with Indonesia but Ethiopia historically had a heavy handed approach when it came to managing its diverse population. Key examples being the forced Amharaization under Haile Selassie, to its violent suppression of separatism to its implementation of ethnic federalism.