Did YouTube lower the bitrate and/or overall quality of 1080p and 720p?

Alright, for a pretty long time I kept seeing pixelation and artifacts in youtube videos, margins more in dark settings than like a year and a 1/2 ago. At first I though my GPU can't keep up while under giant load, that was proven wrong when I finished rendering and had all the spare for youtube.

Next up I though that due to new router, my internet was issue. Again proven wrong when other websites can easily keep up with 4k.

Next up I though new monitor was up to blame. again proven wrong on twitch where the quality was much higher.

some trouble shooting later I came to 2 conclussions.

  1. YouTube silently cut the quality for high resolutions (and possibly lock such behind a pay wall)
  2. I have some fucked up issue that causes YouTube AND YOUTUBE specifically. the only other platform I have problems with are websites that use YouTube playback.