The clip done in regular clothes and on the street (outside where people can see themselves being there) the viewing public can see themselves in those situations in the clip, they can relate to it.
But does not make it real not realistic.
The regular clothes and street like location for the clip may be gives you a sense or reality in what is shown. However it is still a staged
demo, nothing more. There is no show of fighting skills in the clip, it shows choreographic skills.
Maybe these guys can fight, but the video you linked does not prove anything about their fighting or self defense skills.