A factor of 3 difference is still pretty huge in engineering terms though, especially for any mature technology.
Imagine other areas of performance with a 3x difference. A guy who can bench-press 100 lbs vs a guy who can bench 300 lbs. A runner who does a mile in 12 minutes, vs a 4-minute-mile runner. A car that gets 20 MPG vs one that gets 60 MPG (both with the same HP)
Imagine your home insulation and appliances improve such that your monthly utility bill is divided by 3. (say, you were paying $120, now it's $40)
Steel is roughly three times as stiff as aluminum; imagine a fairly thin bar made from aluminum that you can flex by hand without much trouble. Now what if it's made of steel instead? Big difference!
Imagine a new computer with 3 times the performance of last year's model (in the 90's though this probably happened! lol)
Imagine if there was a new humble Ni-MH Eneloop released that now has three times the capacity, thereby tripling the runtimes of your lights.
And so on and so forth.
Point being, the LEDs have a pretty tremendous advantage and I don't think there's going to be any driving force to use incan for anything other than niche, retro, nostalgia markets (like photographic film and vinyl records).
I don't think incan will disappear entirely, but it'll just be some of us weirdos who still use them on occasion