Circus
Part-Time Kano Hostage
So as we know, backdashes use meter from the Endurance Meter. This was probably inplemented to maintain MK's offensive frame trap style while still giving more options for escape aside from just risking a huge combo by poking out.
With the greatly improved walkspeeds and run option too I think this was the way to go.
You could still cancel forward dashes into run then immediately attack, but canceling an invincible backdash into an attack would be pretty OP.