There’s been an awful lot happen in Lost that isn’t really fully explainable - such as the electro magneticity of the island, time travel, disabled people walking, cancer being cured etc etc. But if you think of it in the Star Wars prequel Trilogy - if you try to explain something at its’ most basic make-up then ‘The Force’ becomes midichlorians…
Let’s just look at the final two-part episode and how I believe it’s ended:
Everything that happened since Season 1 of Lost up until Jack’s death, with the survivors leaving on a plane above him all happened…. However, the Alt timeline from season 6 that began in episode 1 with Jack on the flight with Des and ended up in the church at the end was all Jack’s imagination….(hold on)
The alt timeline in season 6 wasn’t ever going to happen, it was Jacks manifestations of everyone he held dearest on the island - all in some way, he had helped fix, and so were leading happier/more fulfilling lives.
The meeting at the church was the end of Jack’s purgatory. It was him that had to let go of the island and he could only do so by fixing everything he felt needed. He was told numerous times throughout the seasons to ‘let go’ but never could. The culmination of each episode’s flashback to the alt world matched with the final episode where Jack helps to ‘fix’ the island by pulling the plug on the energy/ending the smoke monster (in Locke’s body). He was then free to die and let go.
The church scene where everyone turns up is just Jack’s final let-go - because everyone there is fixed in their new imaginary lives that Jack has created for them, as the plane flew over and he dies.
I think this because - everyone is there, even the people who have died on the island previously.
The mention of Hurley as a number 1 and Ben as a number 2 - Jack gave Hurley a drink of water from Ben’s bottle. like Jacob gave to Jack. Nothing more. The church scene between the two is just how Jack imagined them being happy.
Desmond as the constant - It’s Desmond who tells Jack in the last episode that when he is lowered into the light everything will go to a place/time that is good, away from the Island. This is why Desmond is in Jack’s imaginary timeline, getting everyone together to the final scene in the church. (There was no mention of the church - just the concert until Desmond said this.)
It’s also why Desmond says “you were right” when he’s unable to pull the plug on the island himself - Jack had to do it alone, as usual.
I understand the theory that it was purgatory for everyone - waiting for eachother to die before accepting they can move on and find peace due to some of what Christian said. But I guess my view is a bit more Jack-centric.
Lost starts and closes with him opening and shutting his eyes in the same manner.
There’s no way that in season 6’s alt timeline people would just have ‘flashes’ and remember everything that happened in another time/place.
It’s fanciful thinking - but it’s all Jack needed to move on.
And he is involved in most of the flashes in some capacity, often with Desmond bringing it together. His happy life with his son, new found sister and Juliet as his ex, it’s how he viewed things being ‘fixed’ so he was content.
Summary - Alt timeline in S6 Jack’s imagination because everyone being happy is the only way he’d ever let go of the island, having ‘fixed’ it.
