That Reddit will not shut down. It will take the hit and go on and probably make at least some money. Only, it will be a much different place, more like Facebook or Instagram, in that it will be full of ads and less specific information.
It will cease to be a different, often niche space and become just another, more generalized social for a more generalized public.
In short: we, aka the people who migrated, simply are not their intended target anymore.