My take on the story is as follows:

The white guy is big (much bigger than the black guy), and an
experienced fighter.

The white guy took an accomplice along to record a video, so he
intended something worth of a video to happen.

The white guy picks a small black guy, insults him, then puts a show
for the video camera about how he did not mean what he meant, further
incensing the black guy but making a false impression that an insult
was unintentional.

The white guy taunts the black guy some more and retreats.

Black guy is angry, follows him, slaps the white guy in a manner that
left NO mark on his face (so he hit him lightly, if at all), and then
gets severely beaten up.

Does the white man deserve much sympathy here?

Not from me.

He intended to produce a show to post on the internet, succeeded at
that, at the cost of serious injuries to the black bus rider who did
not expect any trouble when he got on the bus.

i