Is the chance high enough for them to make a comeback as a race prominant enough to be a player option? The Orcs don't have a whole province for their own but are still playable. Other than the issue of population, there's also their historic animostity with the Nords, their closest neighbours. Would they just instantly return to their genocidal ways as soon as peaceful Snow Elves made their presence known, or would they tolerate their Mer cousins as much as they do the other kinds of elves? But these are not hard 'no's to the possibility of there being more Snow Elves to rebuild their lost civilisation, or make a new one from the remnants of what was preserved.
So, what I'm asking is, is there room in your heart to bring the Snow Elves up to the ranks of the Altmer, Bosmer, Dunmer, and Orsimer and make them playable?