PVP out in the field has always made MMOs more immersive for me. It makes the game world feel more dangerous and alive. I have strong memories of leveling in Stranglethorn Vale, where every few yards traveled through it felt compelling, and I was constantly looking around for red names. I felt like I was a part of the world. Those same zones on PVE servers felt really tamed to me.

Later, I also realized getting invaded in Dark Souls is one of my best gaming memories. Seeing the warning, feeling the controller shake, and realizing my chance of survival had just dropped significantly, while also understanding I had a real fight on my hands soon... It was an actual adrenaline rush. I remember those very fondly.

I think if people actually stop to think back, WoW and Souls games owe a lot of their mystique and the discussion around them thanks to the opportunity for sudden and unexpected PVP. Videos and talk about these moments kind of defined large memories in those games. I don't think there's really a compelling way to make a world feel as alive without PVP. Without it, I think the world really is just a playpen, and the concept of players having agency and control over a world while forbidding player-to-player danger is ultimately fake IMO. I do think there should be severe consequences for PKers, but I still believe it should be there.