Mortals competitors have systems in place that basically make it so that every player wins "every so often", even if they're garbage, including solo players. Let me give you examples:
This part. You need to feed people wins? Haha. Unless the game massively changed after I stopped playing, there were ways to get kills. I've never met a 1v1 I couldn't run from, should I have wanted to hue.
I post too many words and my brain is overwhelmed by life atm, but my point is that it's not even about winning or losing, even though obviously winning DOES make people stay (look at all of the people who are in MO atm with their cities, gonna pay sub for years prol.) The combat is BAD. Given the limitations they had to work with (ping, for instance) they chose the absolute wrong route.
There are many roles in MO. Not everyone needs to be a 1v1 fighter. The people who put in time to work on their 1v1 craft should see rewards, same as people who put in time to work at other things. You can always find some helpless person to kill if that's your thing. You're talking about fighting the people who are actually good.
I disagree with your psychological assessment of what would make MO good. It doesn't need 'mass success,' that's what Henrik is right about. Dopamine is surviving in MO1. You put guards everywhere and that rush is lost. Dopamine is getting in and out of a dungeon with loot (altho MO1 style, not group, for me.) Even seeing a lootbag of someone who prol did something like lagged out and got mobbed or rode off a mountain is of interest to the mind.
The mind says (I hope I can make coherent sentences lol) I am immersed, I am in a first person game. Then it says DANGER. It says GAINS. You can see a lootbag with something good in it, but then you are gonna turn open pvp, is it worth it? You look over your shoulder.
I've played since 2013ish and I sided with the PvE guys. Barely even fought in MO1, got plenty of enjoyment. I can tell you there are people existing in MO world that are not good at pvp at all and have no desire to be. Giving them the mechanics to scrape a win once in awhile could be as bad of an idea as long parry windows 'but I can't parry 2 people at once,' 'but zergz' game design.
Think of it like this: there is a huge entitlement in MO community. Their refusal to accept the actual equalizer in skill (zerging lol) and whining about it until they tried to add 'anti zerg mechanics (wrap your brain around how that would even work)' is what the sweaties from MO brought. They should have reverted a lot of stuff immediately. I agree with your idea that the surgical duel sim is dumb, and I think we've even used the same phrasing. Just make it NOT that, though. People will get wins if they play. They will get dunked a lot, but they will soldier on like tru MO vets and then learn. The ones who don't will quit. OH WELL.
TLDR from a combat standpoint it's the wack melee system that someone thought was going to 'raise the skill level' (and if it did anything, it just raised the floor, which like I said is blah) NOT winning and losing, that is turning people off. Like I said before, I talked to many people in beta and they all said the same thing, I like the game, but the fact that parry is the norm when you swing... people quit over that.
PEOPLE CAN STILL BE GOOD AT MO2 WITHOUT BEING ABLE TO PARRY EVERY ATTACK. People who put in thousands of hours are probably hyper resistant to change, though. I didn't because I had a feeling they would wise up and realize how bad it is.
I contend that once they make melee combat GOOD, the game will actually be higher skill than it is now. It needs to be cut throat. If you just stand there and wait for your opponent to make a move, they need to be able to overwhelm you quite easily, making it so you have to move... like in a fighting game. Imagine if you played a fighting game like people play Mortal. The only dopamine rush people are getting from MO2 combat are the people who have done so many hours of duel practice the ting of the parry probably makes them feel like they are winning a gambling machine prize. Or people who are just on that I DUNK U dopamine rush, and those people are willing to go thru 'great lengths' to get that feeling, if you know what I mean.
Also there is the largely ignored crafting and PvE/life sim aspects which are lacking from MO2. Again, not everyone has to be a fighter. People need to be able to contribute to the world. So yea, I def think that the people who quit cuz they can't win are just not built for MO. They don't understand in a game like this, there are many different kinds of winning. Maybe 1v1 isn't your cup of tea, or maybe you wanna put in the thousand hours. But I can tell you I've personally seen plenty of people quit before they even put in serious practice because they looked at the combat and were like heh.