It is an eye opener. I would like to have seen what led up to it that made the driver get out, maybe bumped him with the car?
By the way the knifer adjusts his grip it appears that the knife is small. He definitely charged the guy. Lots of left sided body hits.
The cab driver is in a tought spot due to the other guys reach being able to create striking distance.
A clothing grab is tough to deal with...trying to release the grip, move, maybe counter...
A bunch of things to think about here.