The "official" answer I keep hearing is they're only actually dead in the last episode, which makes everything about it cheap and tacky, so I reject that.
But there's an alternate timeline shown where they never were on the island as well, iirc. And it's all just weird. You can't be internally inconsistent if there's never any established consistency.
I enjoyed it like watching a train wreck in slow motion and getting to discuss it with people as it developed. But it clearly didn't have enough of an impact on me to remember anything worth remembering except "Don't tell me what I can't do" and "You all everybody."