Dude, they never were going to answer those questions. Do you think anyone expected someone to face the camera and say, "Ok, the light is god. He lives on the island but the devil lives under him in the cave and get out and blah blah." We're lucky they actually showed us ANYTHING. As you pointed out, they dead ended us for years with BS that they can't/won't answer. Its like people defending Lucas and his bs that he knew exactly how the 6 Star Wars films were going to play out from day one. No he didn't and neither did the clowns writing lost. They left so much unanswered... so so many questions... so very tired...... what was my point? Oh yeah, STAY OUT OF MY BOOZE!
Those questions were never going to be answered but as Azmontana correctly points out:
The problem with the show is that there was no end game in mind, the end game was an after thought and because of that all the discrepancies built up and nothing was really answered!
When they had an end game in mind they should have simplified it instead of complicating matters with more bull****!!
So those questions should never have been asked in the first place. After building up three years of mythology and announcing an end date (down to the episode) what the writers should have done is start explaining some of the stuff they introduced on the island. Three or even two seasons would have been fine to tie up that stuff. Instead, Dharma and The Others (the main plot points until then) were cast away in favor of Jacob and we're left with Season 6.
The whole reason they announced an end date was because ratings were slipping. Viewers were tired of the unanswered questions and the television powers that be thought if they gave the fans a date to look forward to, they'd rightfully assume questions would be answered along the way and we'd have a satisfying finale. So after dipping in Season 3 or 4, ratings went up the past couple of seasons. But they played us for fools and didn't answer hardly anything, just introducing new mythology and new questions that simply weren't needed. I reckon if fans knew this was how it was going to end, so many would have dropped off along the way that it would have been cancelled before Season 6 was allowed. Instead, their bet on an end-date keeping eyes glued worked, and now we've got half of fandom happy and the other half pissed.