you're not wrong, but Chip Kelly was a failure in the NFL and it's no secret that his system was terrible for Murray as evidenced by his mini-resurgence in Tennessee.
Besides that, there's a few other factors that play against Dallas this go around. Back then we had Romo who could atleast make ty teams compe ive whereas Dak struggled without Zeke in 2017. This team really needs that running game to get going or else they're not even a .500 team. Also, our offensive line had an aura of invincibility back then which isn't there anymore. That was the main reason Jerruh told Murray to get lost. They're basically throwing away next season, which is risky considering they only have a 2-3 year window right now.
On your last point, I'm shocked the Rams gave Gurley all that money considering he was outplayed by CJ Anders
n in the postseason. Instead, the Cowboys running game was a mess whenever Elliott would leave the field