Solid state drives are very fast. Most programs can fit in cache for fast execution. Is there still a need for large amounts of RAM? Website are about the only thing that still rely on it.
You will always need random access memory, the question you should be asking is whether ssd and hard disks will ever disappear.
http://www.theregister.co.uk/2015/07/28/intel_micron_3d_xpoint/Websites might be the only thing you use that needs a lot of ram, but anyone serious with digital photography will have a different experience.