few Simulacrum Spliters in Delirium Maps

I am finding very few Simulacrum Splinters even though I have fully specced my entire Atlas Skill Tree for Delirium. In 15 maps that I clear completely, I only get around 3 to 7 splinters. Sometimes, however, I get 20 splinters from a map. I don't understand why, and above all, it is very frustrating to reach 300 splinters at this rate. Does anyone know why this is happening or what I might be doing wrong?

I've ran about 30 to 40 deliriums, I have seen 0 splinters. 60% of them on t15, with ~100 rarity

Delirium is so sooooo soooooo very dead, even more than the temple.

In the Delirium Atlas tree, you can see the final node in the top-right corner. You need to allocate that node after completing the quest; only then will you start getting splinters. However, as I mentioned, you unfortunately receive very few of them. In its current state, it's not particularly fun.