As a cyclist and driver, I have looked at the video a few more times.
The cyclist was a complete idiot trying to overtake at the lights, he wasn't even in the zone for cyclists.
When they both reached the next set of lights and stopped, there was swearing by both people, and the cyclist thumped or kicked the lorry at least four times - that was the catalyst for what happened next, because if anyone kicked or thumped my vehicle then I would get out as well.
With both people on the road, the cyclist attempted to puch the driver at least seven times, during which the driver simply held on to him to avoid being hit.
The driver did not kick the cyclist, but used a single leg sweep to force him onto the ground so that he could be subdued.
If the cyclist continues to ride like that for much longer then he will have a very much reduced chance of survival.