Of course.
But the game also gives the players way much power compared to the NPCs
So one that is aiming to get some fun by interacting with the NPC will get totally stomped by other players.
And if they prepare for other players, NPCs will be no fun.
It's worth mentioning that, since ED has no difficulty sliders, there is no way around this. There will always be an tiny minority of very good players that will stop the vast majority of casual pilots or the regulars that are in no way interested to git gud in combat.
Anyway, getting back to players getting stomped by other players, they already acknowledged that's a big issue by:
- constantly enforcing Block over the years
- introducing the starter systems where one is not allowed to kill other players. Technically nothing stops a player to kill another player, but if they do it, they get removed from the Starter Systems.
And these aspects, especially the last one - booting murderers from Starter zone, can be used as a base for an Open PVE mode.
Simply applying the same rules - murderers lose the access to that Open PVE mode.