Menelik was also the same guy that sold Eritrea to the Italians so he could weaken Emperor Yohannes IV's rule as well as strengthen his own army to secure his own rule. Menelik was a great leader but he made some big errors too. Mainly not pushing the Italians out of Eritrea when he had a chance, selling off all the coastal lands Ethiopia had to the Europeans, not switching from a slave based agricultural economy to an industrial one when he had a chance. Still tho, I'd take Eritrean propaganda sites with a grain of salt. They absolutely HATE both Menelik and Haile but it doesn't help that semitic Eritreans are Tigrays while Menelik and Haile were semitic Amharas which is their long time tribal rival.
As far as that quote goes I'd need a link for it, not to say it would surprise me tho cuz Ethiopia was a slave society when Menelik was in power and Haile abolished slavery in the 1920s in order to gain entry into the League of Nations. Race in Ethiopia isn't like race in the Americas, you had the semitic tribes (Amhara/Tigray) which were more mixed and lighter than their southern counterparts the Cushytes and Nilotic peoples which are dark and have all the features you'd expect of Africans and so the lighter peoples were near the coast so they had the means to more modern technology than the tribes of the south. With that technology also came racial ideas, Ethiopians were referred to by cacs of that time as the most advanced form of Negro and at best semi-barbarous due to some "caucasian blood" and perhaps it was this that brought about those feelings.
Menelik and Haile both made the mistake of thinking these Europeans respected Ethiopia's history or sovereignty or didn't look at them all as black. Thankfully they were sharp enough to keep the country from being colonized, but the slave industry that'd gone on for centuries set the country back majorly in terms of economics and the racist ideas that European trade partners gave us fukked the racial ideals of the country.
Really this is too tricky a subject, its not as simple as black and white.