Its a 5/4 body with first strike for a total mana value of five, which is already pretty decent, but it also consistently creates tokens and can eventually become a way to draw cards
In a format dominated by fetch lands and tutors, its much harder to stop searching libraries than it is to stop drawing cards, and as such most people will seldom play around a resolved Archivist of Oghma
Saddles are optional to make the likes of Vryn Wingmare, Shepherd of the Clouds, and Moonshaker Cavalry run wild
Now take a look at the MM17 mythic offerings by comparison
Note there are no restrictions here beyond that any counter counts from anyone's stuff, and then when it dies you can send them to a dork like your Commander or other stuff and then this is tucked
Summary Starter Commander decks cater to new players with simple mechanics and low cost options - around $30