Their future has been the major driving point of the Forsaken narrative for a long time, actually. Ever since Cataclysm. We’ve only really gotten to experience it through Sylvanas but that concern over how they can continue their species (because losing population means they WILL get exterminated by enemies eventually, making reproduction less about legacy for future generations and more about preserving themselves now) and what they must become has been at the forefront of their lore ever since Arthas died and the Forsaken collectively went “What now?”
Cataclysm their story was mostly about their place in the Horde and how they can expand. Garrosh treating them as fodder and Sylvanas sacrificing some of their limited Valk’yr to save herself were both wake up calls that the Forsaken need to do something to progress as a people.
In Stormheim that was also Sylvanas’ stated goal. To find a way to keep the Forsaken as a people going strong.
Unfortunately we both know that Blizzard only takes toys out of their toybox to play with them once in a while unless they are some variety of human, elf, or orc so the Forsaken beyond Sylvanas haven’t had much of a chance to explore this theme of their race.