Hey Commander. Disclaimer for this comment, put your tinfoil hat. I hoard essence to get Daredevil's when he gets his T4. So I made this deal with myself that I only spend my essence when I reach a certain threshold; let's say 90k, then I spend essence until I get a personalized artifact. After that, I push the threshold up, let's say 93k, so I can keep hoarding. What I experienced is that after I went over 100k my luck went to the drain. I started to need like 13k average to get a 3 star artifact for a garbage character. And over and over again, it made hoarding essence a miserable experience. After that I decided to be under 100k at all times and when I pull, I use to get the average that content creators get when they spend like 30k they hoarded. I may have been shafted in a very unlikely way, but my conspiracy theory is that the drop rate falls immensely once you get to 100k essence or so, and this video just reinforced that theory.
If I were a conspiracy theorist I would believe that your luck is being targeted for the amount that you are gambling. That would be the only way to explain your terrible luck.