No, it seems Tesla has not implemented stop signs yet.
As the video alludes to, it seems that the current enhanced summon is really just an exercise in "free space path finding". The focus is on path finding and recognizing the "driveable space". Tesla is training the vision NN to know that this area of asphalt is driveable but that curb or grassy area is not driveable. This is a necessary first step especially for Tesla that relies on cameras for perception. Before you can get to road signs and such, the car has to know where it can drive. And again, Tesla has to rely exclusively on cameras for this which is why it is taking time to train the vision NN. The current Enhanced Summon is primitive but over time, it will get better. Once Tesla nails the "free space pathfinding" part, they can incorporate stop signs, traffic rules and auto park and then enhanced summon will be able to self-drive and self-park on its own.