I think Mahomes is a unicorn, someone who could be an excellent pure pocket passer but also can run as well as any QB ever which makes him really dangerous. Hmm, TB12 just took him down in the last Super Bowl, and took him down on his way to winning it all in 2018 as well. +2 for the pocket passer who can't run.
I worry about running QBs as they age. I know the NFL does everything they can to protect them, but strange things happen when you are on the move. Cowboys stank last year because Dak Prescott injured his leg on a running play. Now we'll see how willing and able he will be to run this season. If he can't run any more, can he adapt to being a pure pocket passer?
I think the league is going more run heavy because a lot of the college programs just find it easier to implement a running offense. Passing requires a lot of coordination, timing and intelligence, all of which takes a lot of coaching talent and time. Since we have so many QBs leaving school early, they can't invest as much in each of them.
In short, I'm not worried because the rest of the league is getting QBs that can run.