Allowed his opponent to close the distance when he had a tool which needs more range.
Range can be managed by movement – he’s completely stationary.
Flat posture, straight back, very likely standing with knees locked straight, does not appear to be in any kind of stance which would prepare him to respond in the split second required to move, defend or attack. His opponent constantly adjusts.
Allowed opponent to grip his wrist. Difficult to swing baton effectively when grappling starts. The grip even from this position may allow opponent to stay off-centre when the baton swing comes.
Furtive glance made by opponent is a huge warning sign. He has already decided to attack at this point and is looking for witnesses, other enemies or allies which may factor in to his decision to go ahead.
Even if he decided to use the baton, it’s a poor weapon. Law enforcement use this as a method of pain compliance, and often need to move to other methods when it fails. Striking the legs is unlikely to instantly shatter kneecaps unless you’re very lucky/unlucky to hit that spot. You’re only starting the fight, not ending it. Swinging to the head would be a different matter.
Compare the above (pain compliance) to the punches thrown to the head (incapacitation).
Baton man seems to think intimidation is enough to keep him safe. The baton is like some kind of force field, everything else can be ignored.
From this position, when would he decide to use it? Once the fighting starts? Too late, too close. When the man fails to step back? This may be considered unjustified assault. Baton man then made a threat to seriously harm, which prompted an aggressive response. He put himself in a situation which is very difficult to win.
Knives do not immediately incapacitate – often, a person who has been stabbed is able to continue fighting for long enough to successfully retaliate, even if they die soon after. This makes knives both a poor choice for self defence, and a good choice for murder. A horrific way to fight since ancient times.
An important point to learn from this video: striking is an effective response to a knife attack, assuming that you are a capable striker. Many people tend to focus on the knife and fight to control it, not realising that this is as good a time as any to punch the face.
Most people tend to overestimate their fighting ability. This man is off the mark further than most when he is surrounded by 5 youths (including the one operating the camera). He initiates the violence (flicks a cigarette at one and pushes another) but takes no appropriate action – allows himself to be surrounded, does not move, does not position himself correctly or attempt to isolate and incapacitate his opponents. He appears to falsely assume these youths will cower and back off.