since for whatever reason ancestral items don’t drop that often for me, and the last thing I have to do is salvage 100 of them. It might have to do with the Torment level I’m on

I'm on Torment 4 and yeah, they don't drop a lot. If you're on a high enough difficulty, Ancestral Uniques probably drop more, since you can farm the Uber bosses, who basically only drop uniques. I think that objective was the second to last one I finished for the journey (the last are the 5 Helltide Commanders, which I don't probably won't do).