There could be many people that realised his scholarily quality but the late Prof. Mesfin Woldemariyam, whom I can't sign off as somehow associated with the political stand of Dr. Abiy, comes to mind. He didn't hide his appreciation of the intellectual quality of Dr. Abiy from the get go.
The other known scholar is Prof. Alemayehu Gebremariyam of California state university (?, I am not sure about the name of his university) who also recognized the intellectual capacity of Dr. Abiy early on and stayed the course so far. He is also one of the great patriots of Ethiopian nationalism.
He could be among the few who are not motivated by the personal gain or fame in jumping on the bandwagon of "the change" and swayed in every direction of the day's wind. I was one of those people who considered the Prof. a sort of biased opportunist earlier, wrongly.
Objectivity is the rare commodity in the current political field of the country, where everybody get's up and acts an analyst of politics.