I dunno.... While the injury itself is a problem, just think of how Bryan's injuries affected the company.
2014 - had to vacate the highest belt in the company due to injury
2015 - had to vacate the second highest belt in the company due to injury
While that may not sound like a big deal, they had months and months of storylines planned that had to get thrown out because of Bryan's injuries. And then there's the fan dynamic into the situation - fans revolt when he's not a champion, when he is a champion, he has to forfeit the belt shortly after winning it. Isn't it easier to say "you know kid, it was a good run, but it's done now" than to repeatedly put somebody out there who is, at that point, an established injury risk who will throw your plans into turmoil the second he's on the shelf again?
In a business sense, keeping him around in a non wrestling capacity is far better than ever putting him back in a WWE ring.