I believe a lot of the problem is that it's easy to associate something as a cause when you see it, when there is not any proof that what you are seeing is actually causing the problem. For example, you see a dead game and there are walls everywhere.. so naturally it's easy to combine A and B and say "the walls are the reason the game is dead", when you do not know whether or not there is actually anyone playing behind those walls to begin with, and even if there were, that simply having more players would cause the game to feel not dead. In a more scientific term, you would say that correlation does not imply causation. The two things may appear related but there is no definitive proof that they are.
This is exactly why I am so adamant to defend the walls being in the game, because in MO1 there were never many players to begin with and there are an extreme amount of variables which determine periods in which the game feels alive and the game feels dead. For example, when you look at Steam Charts the game averaged around 200 players, and sure you can indeed make an argument that there could have been more players than that (since the game had it's own independent client), but even in the case where that's true the world size of MO1 is massive and there's a good chance you will never see most of those players unless you frequently travel across the entire world because even 300 players is basically nothing.
As such, that's also why I felt a bit skeptical when they said they were making MO2 even bigger. The bigger the map is, the less likely you are to see other players, the more dead the game feels (even if the game is actually not dead). That is actually the complaint players have right? Game is dead, they cannot fight anybody.. BUT! It's the walls fault, it can't possibly be anything else! That is how the players of this game react. The reality is, MO1 was dead for many other reasons and over the course of my 3-4 years playing I have yet to find that walls are the true cause of the problem (and I've always enjoyed having some form of protection against bloodthirsty players).
Look at videos such as this for example:
This is a true impression of what the majority of people in the world think about Mortal Online. It's not a good impression. If you look at everything this guy talks about, he doesn't ever say anything about walls. He's not the only one, when Asmongold tried out MO2 for the first time, he also had many of the same complaints and then some.
And to put things more bluntly, Mortal Online feels dead not because of walls, but because the game is, and has always, been dead. Walls are just one blip on the radar amidst a million problems with the game, from the political drama and turmoil, bugs, lack of safety for players, players not able to understand the game, and more. If players want the game to not "feel" dead, then first the game has to actually not be dead. A higher population means there will be more player activity, and more player activity means you will be much more likely to have interaction with other players.
That's the reality of Mortal Online. Don't tunnel on one single aspect of the game (walls). Personally I do think the walls in MO1 are very unbalanced, however I would never go as far to say they are the reason the game was dead. Mortal online was always dead, far before walls existed and all of the players ignore the huge elephant in the room for some reason to hate on walls.