1. The first thing that I noticed is that they're wearing gloves.
There's a reason that we wear gloves in competition, no matter the weight of the gloves, and it isn't just to keep your hands protected. If that were the case, I would think that the outer shell of a glove would be just as hard as a bare knuckle fist.
I could only imagine what would've happened to Muhammad Ali if, in that famous fight versus George Foreman (where Ali performed the "rope-a-dope"), they would've fought bare knuckle. I believe the chances of someone dying in that fight would've certainly increased to 90% or greater.
So if I'm really trying to hurt you -- F the gloves.
2. The second thing that I noticed is that this is a fixed fight, in a fixed setting.
In the street, I'm looking at things in a self-defense situation... I'm not circling a room or any area and trying to defeat you tournament style, and I'm not minding the limitations of the room, space, or area that we're in; There are likely no limitations, such as confinement to the quarters (so to speak), and there is not likely a "ring of fire" with tigers on chains surrounding us and keeping us confined to the space that we're in. If I find myself trapped in any kind of confined situation, I'm looking for the quickest escape route out of the situation and/or doing what I have to do to stop you, even if that means that I have to go last-resort and use whatever improvised weapon/s that I can get a hold of to apply the most reasonable amount of force -- within legal limitations. Moreover, in my martial arts style we put in a lot of dedication to a very broad syllabus in order to use every little thing that we have at our disposal to get the job done as effectively as possible and in a way that keeps us from being harmed as much as possible. We go for the throat, we go for vital areas of the body, all without hesitation. I haven't been taught to do so by anyone yet; but (especially with grapplers) I bite, headbutt, gouge, claw, scratch, grip the trachea, and go for ripping of flesh (especially the ears). Goes back to the limb destruction philosophy that we practice in Kajukenbo Arcos Method; whatever you give to me, I will take away. And on top of all of that, I use any other type of weapon that I can get to -- and I practice and train to use it as effectively as my life depends on it.
For the ring, I don't even train this way; for the ring, I don't need near the amount of technique -- because in the ring, my life doesn't depend on it.
I perceive the "fight" in this video as nothing less than a ring fight.
3. The third thing that I noticed... No disrespect intended against the black belt but, aside from points 1 and 2 (especially #2), judging by what I'm seeing in the video, she doesn't even appear to have much going for her in terms of technique. Ideally, that is what most people are probably judging at face value ("Who has better technique? Who can use more/better technique to defeat who?"). Even with it being a fixed setting with a set of rules clearly being abided by, I'm still not seeing the technique on her end.
In my opinion, this is not a full-contact fight with no rules. In my opinion, the alleged "street fighter" is not really being a "street fighter" in this video.
I'm only a 9th Kyu (White Belt), so take my opinion for whatever it is worth to you, but I fight black belts and get my *** kicked by them on a regular basis. We DO go full-contact, bare knuckle, and we hit each other hard. I don't go home without bruises, blood drawn, and having the wind knocked out of me many, many times. The only thing that we use for protection is a cup and maybe a mouth guard. In my opinion, the black belts that I train with would mop the floor with both of the two fighters in this video with ease -- and I put all of my faith in their ability to do so by themselves against both of them at the same time (1v2).
Though again, that is only my opinion -- so take it for whatever it's worth to you.