That very first video is a perfect example of how you're supposed to play the read option these days. If the T blocks down the DE is supposed to crash down too with the LB taking QB duty. Micah and DLaw have done this many times this year and got called out for not being able to set the edge, but its a LB issue, not a DE issue.
Also on that play either Dak is handcuffed and they dont want him to run at all, or it was a terrible read.