Honestly i doubt its that hard. I started with 24mg a month ago (used to smoke a pack a day if not more of "lights" or 0.6 nic) dropped down to 18 though still have a few juices at 24 and some 12. Most of the time 24 is sickening to me even though it was barely there the first few days, even 18 is too much sometimes..and thats within a month of quiting. Though it varies from one person to another, could take you 3 months or 3 years I guess, but at this rate it is possible. I actually just had a 14 hour flight with no vaping, and I did not feel the stress or the urge to vape/smoke that I used to have. So it seems to me that my symptoms of addiction are fading away surprisingly fast, and surprisngly easy...I just wish i brought less 24/18 with me and more 12 since nicotine is starting to become disgusting at high amounts to me.
The big question though is, if you can live with 0 nic, then why vape in the first place? Personally I always got satisfaction from blowing smoke...also some flavors are quiet good and reduce my craving for sweets, but on the other hand many people here care more about quiting or enjoy nicotine anyway, so people either quit vaping after a while or stay at 6 mg or lower. The ones who exclusively vape at 0 nicotine are a rare group...since, at the end of the day, most people are into smoking/vaping for the satisfying addicting chemical component, even if they enjoy the other things that come along with it...
I like to compare it to the dog meal and bell ring experience they taught us at school. The dog drools when the bell rings cause its assigned to the satisfying chemicals he recives with it (food). He might even start to love the sound of the bell, but will he continue to do so if he no longer receives food with it/wants food?
Short answer, i think it is very possible to go 0 nicotine, but pointless to most people since they either quit completely or keep taking a minimum amouny of nicotine for the satisfaction it gives even with the absence of the addiction.