@myrm Of course the logic goes both ways. Everything said on the forums is speculation whether something is easy or difficult to implement, or whether system X or Y is being used. If you looked at the rest of that particular post, you would see why I hold the opinion that extensive re-work would have to be done to implement PvE servers as well as my other comments in the thread. As with any argument, I took my opinion and applied logic to justify that opinion. Just like everyone else in the thread.
The base game may not have been developed with a PvE mode in mind. Systems implemented to track damage may need more work than flipping some boolean switch somewhere. As such, added systems that rely on the base system will have to be modified as well. And of course the more complex your systems and their relationships to other systems are the more difficult it is to implement changes that are contrary to the core design of the game.
Player damage may not be difficult to switch since the only thing that doesn't track damage ownership are the gunpowder barrels. The ship damage system will need the most work however. As of right now, it doesn't appear to care who or what caused the damage. As I said earlier, ship damage appears to be in the realm of everything is environmental damage whether it is cannonballs, ship models, the land, or gunpowder barrels. This is evidenced in that you can sink your own ship with the above methods.
But the main point I would like to make is that just because something seems simple to implement, it may not actually be the case. Hence Rare not implementing PvE servers yet if it is feasible to do so. Doing things the "quick and dirty" way isn't always the best solution.