LG has added a feature called Fine Tune Dark Areas to over 70 TVs as it aims to reduce raised black levels, especially on OLED panels. LG intends people to use the feature when using VRR on an enabled PC or games console.
https://www.notebookcheck.net/LG-enables-Fine-Tune-Dark-Areas-feature-on-over-70-TVs-to-mitigate-VRR-raised-black-issues.528509.0.html
I have downloaded the 3.21.80 update on my Nanocell 90, but there is no "Fine Tune Dark Areas" feature under the additional settings tab, only the usual settings. I unplugged my tv and rebooted it, nothing still.