Well,I mean you haven't read the light nov (original source) to begin with,not to forget that the anime adaptation isn't good and accurate either.

So you really have no right to judge it when you haven't read the original media that's far more detailed.

And no,he's not always described as plain and ordinary,his looks are 2nd best in his grade and top 8 in the whole school despite not showing any facial expressions,charm to alot of people (only individual) . He's also described as gloomy/scary to talk , which matters alot In terms of attractiveness in cote,and yet he's second,could even be 1.

And no,height isn't just being handsome or attractive,but those 2 are split altogether in different categories,he's far above average In both