Very doubtful. In my personal experience I have found that emulsion binds/sticks and eventually weakens over long-term storage (I have had Velvia 50 and 100F in deep freeze since 1997 as an experiment). When loaded, the film commonly jams — at worse, drive torque can rip a bonded emulsion. This is not endemic to just Velvia, but many films, including Ilford Delta 100, 400, T Max 100 and 400, Provia 100 and roll film (because of the inclusion of paper backing there can be absorbtion of moisture into the roll if improper acclimatisation procedures are not followed from deep freeze to ambient room temperature). Realistically 5 to 6 years of storage and periodic removal into ambient temperatures is the best practice.
The remaining Velvia emulsions may be around for a few years yet, but the E6 process required to bring the images to life is diminishing in availability, save for home users. This in my eyes is the major threat, not the availability of E6 films. Once the process goes, demand for E6 film will I imagine drop very sharply and no amount of hording or insurance against "discontinuance" will reverse the problem. Summary: use Velvia now while E6 processing is reasonably easy to obtain and enjoy the results.
The issue is something called condensation, warm air holds more moisture then cold air, so if you take something like a roll of film out of a freezer, the air immediately around it will be cooled to the same temperature, so the moisture condenses on the film. Dampness can weaken the adhesive that holds the emulsion to the base, and make the emulsion stick to itself. The way to prevent this is to get one of those vacuum sealing machines, put a roll into a bag, and seal it. This removes all of the air from the bag, and seals the bag to the outside of the roll. Condensation now happens on the outside of the bag, rather then on the film itself. Because there is no air inside, there is no moisture inside, so you can toss it into the deep freeze, it can stay there for decades, without any problems. To use it, you take the bag out of the freezer for 24 hours, to allow it to completely warm to room temperature, before you open it. I suggest you write the expiry date and the freezing date on the outside of the bag, so you know how long it's been frozen, and how long it can remain thawed, before it will start to show the effects of expiration. I also suggest you keep them sealed until ready to use.