The way I see it, it really depends on how you devs want your game to be. If you want it to be an easily exploitable game by having multi-accounts or you just wanna be as profitable as possible, then allow multi-accounts. If you want your game to be enjoyable for regular players and not require the need to have multiple characters and have to balance that shit out every time you play, then make your systems not be affected by multi-accounts. Personally I put multi-accounts up with botting, same damn thing, you have a bot sitting some where doing shit for you while you play another character, same shit. Doesn't matter if you click the button yourself or have a program, still just a throw away character sitting there doing shit for you while you can do other stuff.
I hope to play this game with my family (GF and son) but if this is how it is decided to set the rules, I would wager we won't even bother since the necessary playstyle is just not fun or immersive at all. Up to the devs but I don't see the value in it at all other than the cash grab and prefer not to have a system that supports said gameplay.
This is where properly designed game Albion Mall mechanics solve these issues without even broaching that grey territory. For example naked scouting you put a black screen on death (a great decision) which prevents sitting there dead and seeing what's going on in red territories. In addition, reward splitting (such as fame) already reduces the amount of fame gained and splits it up between party members which means even if they are multi-accounting they're doing it slower than those who aren't. In extreme cases where a person might be controlling 5-10 clients at the same time a properly designed adjustment of fame/silver rewards for those who bring too many players to content (IE: bringing 5-7 to solo content, or 10-20 to 5 man content) would also reduce that as well.
I can already tell you that if device ID does not stop really stop multi-accounting, then there is really no proper way for us to stop it, unless we turn our company into a digital identity verification provider and asked people for driver's licenses and passport copy if they want to play - which of course, is not feasible.