So during those 670 hours, when has Elite became an experience and stopped being a game?
Unless it was just "an experience" from the very beinning - and if that's the case, then my question is: why would you spend 670 hours in something that's just "an experience" for you? What is so engaging about that "experience" that keeps you coming back to it?
And if you answer that - you may realise that Elite is indeed a game, not an experience and the game is that, what keeps you coming back to it
Also, as a side comment, I think people like us (I have well over 1500 hrs) are either complaining or not happy with the game, as we played absolute shedloads out of it - and there is just not much left in it for us. Hence the feeling that there is no game or no story or no <insert what's missing in Elite for you here>.
Yes, guilty as charged, I have been criticising the game lately too (I'd like to think it was constructive criticism rather than pointless moaning and whining), but just recently I have realised that maybe it's not the game, maybe it's just me having so many hours under the hood that I have simply overdone it.
And the truth - as often is the case - is probably somewhere in the middle of all this