It's interesting that many of us assume vapers will chose to become coil builders out of necessity when most are not currently doing so and have little idea of what Ohm's law is. We at ECF are typically much more involved and knowledgeable than the mainstream ecig user. Without heads or clearos, many will revert to smoking should availability be interrupted.
I hope they get informed and do stock up over time for that possibility. I agree that a two year window should be adequate for most to wean themselves off vaping or choose to start building.
I've already started upon coil building. Next for me is some basic DIY juice mixing. I plan on attaining a Kanger Dripbox 160 & possibly a Dripbox 60. May get and keep a small stash of 18650s on hand. Also looking at possibly finding a decent & reasonably safe mech mod, a/ a few Velocity V2s, Velocity Minis. TEMCo will continue selling resistance wire and cellucotton rayon will continue being available. The big issue for me will be the nicotine & I may attain some pre-mixed 50/50 unflavored 18mg base to help me start mixing, keep it stocked.
All of the above is tentative & not actual planning. I have no plans, not ever.