So two things to address here- first the Bills have never been committed to a consistent rush attack since Allen became starter. I believe it's a combination of factors including the state of the offensive line as well as philosophically they don't believe in it but it's been a consistent theme carried over from Daboll, not a Dorsey specific issue
It sort of touches on a front office that believes strongly in their offensive philosophy which they don't really prioritize (correctly, imo) the kinds of things like the bolded because they're outdated and -ev. Last year the teams with the highest average drive time were the Packers, Steelers, Raiders, Falcons, and Browns respectively. These are bad offenses. They're bad because they don't score points or gain a lot of yards...because they don't have good passing attacks...because they don't have good QBs...so they run the ball a lot...which takes up a lot of time/drive