Vapers are not the center of the universe. Probably the majority of 18650's are used in devices not related to vaping. There are millions of devices of all kinds that use them including mods. As long as there is a demand for 18650's they will be available for sale.
The only mod I use is a Pico. A 3000mah battery gets me through a day.. There is no reason for me to be carrying a larger mod so I won't ever be needing the new larger battery. In the event that there are significant advances in Li battery chemistry (seems unlikely) there will be an effort to incorporate that in 18650's because there are already millions of devices that use that siize.
The only mod I use is a Pico. A 3000mah battery gets me through a day.. There is no reason for me to be carrying a larger mod so I won't ever be needing the new larger battery. In the event that there are significant advances in Li battery chemistry (seems unlikely) there will be an effort to incorporate that in 18650's because there are already millions of devices that use that siize.