“We see that the TBW has increased drastically, from 120TB (500GB QLC) to 4,000TB (120GB pSLC), which is an increase of over 3333%, more than 3000 percent.”
A 500GB Crucial BX500 is rated for about 120TB of writes. Flash it to run in SLC mode and it holds 120GB but survives about 4,000TB. Sustained writes go from about 50MB/s to nearly 500MB/s. The cheap QLC drive was always a good SSD with the endurance sold off to hit a capacity number on the box.