A bigger screen shows that the sill plate does exist in that installation.
I am aware that sill plates for SE cable are manufactured, but I am unaware of any specific NEC, UL, or manufacturer requirement that they are to be used. They sure make for a more “finished” appearance often times, and may provide some mechanical benefit. That said, in areas where load side SE cable accepted, I’m not sure what would compel me to use a sill plate, save for the fact that they exist and it “seems” like the thing to do. I am well aware that cable that is exposed to physical damage requires protection, but I’d be hard pressed to say that the last 4" of SE cable before it goes through the wall is any more subject to physical damage than the other 4 feet up to the meter socket.