IMO, PL didn't kill anything. I think the experience rate is more to blame. Even for LS mates and friends, I'd be hard pressed to PL if leveling was more akin to pre ToA FFXI. PL isn't popular because it is possible, because it always was. PLing will always be attractive to people wanting an easier time leveling, but there's another reason its exploded.

It's popular, because now the xp given from mobs is over triple and the chain and link bonuses compound the increase.

Does PLing need to be addressed? I think so, but I think the xp output is what really needs looking at.