For the question why they are considered a race of man and not beastman I think we may also want to look into why Dwarves who are Lalafel are considered beastman and not man. This leads me to believe that beastman is less based on looks and more based on whether that race follows modern man society norms and I think a big one would be do they worship a primal.

Though Hrothgar are beastly in appearance they most likely have structured their villages and culture in a way that is very similar to other man races and don't worship a primal.

This is also a side thought but all beastman have genders that are near impossible to tell apart from one another. Lalafels basically look the same no matter the gender. Height being the only real distinguish factor between males and females.