I'm not going to lie, but as much as I would disapprove of bloodsports and find the idea of people killing each other for entertainment abhorrent, if I had the opportunity I would probably watch at least one or two bouts out of a morbid curiosity, especially if they featured melee weapons that I found interesting.
I've enjoyed watching MMA for over 20 years and cut my teeth on the earlier and more brutal Vale Tudo events, and I also enjoyed the the concept and fight scenes of Deadliest Warrior (despite how full of bullshit and biased some of the match-ups and idiotic 'expert' conclusions were), and my morbid curiosity surrounding death caused me to recently view an ISIS video of some guy being run over by a tank, so if I had the opportunity to watch a combination of the three, I can't say that the injury or deaths of the random strangers involved in it would be enough to dissuade me from watching.
That's not to say I wouldn't be terribly conflicted having watched it (even more so if I enjoyed it), and I certainly would never feel right about supporting such a thing financially (i.e. paying to watch it) or even giving my public or private approval (such as a tracked view and a like on an internet site), nor would I oppose such a sport being banned again, since it's obviously not a good thing.
Also, in theory I can't imagine that even if I watched a few bouts that I would enjoy following it on a more permanent basis because I don't like it when one of my favourite fighters loses or if a character I like in a film or TV series dies, so I think the concept of permadeath in a sport would be quite off-putting to me and most fans.
In reality (i.e. not the myth that ancient gladiatorial combat was to the death every match) it would be really hard to maintain interest in the sport or fighters if they died or suffered career ending injuries every bout, since even the most skilled talent would be quickly whittled down, then the entire sport would be reduced to amateur bush league athletes pretty quickly and wouldn't be worth watching (because the time it would take to train a good and entertaining fighter would be eclipsed by the scheduling of modern sports).