We are running a small experiment where 0.3% of viewers will see an auto-generated thumbnail, instead of your custom thumbnail. We are not removing the ability to create your custom thumbnail, but we hope to gain insights on auto-generated thumbnails for the future.
From a creator's pov this is literally taking their work and throwing it out the window. From my pov its also dumb coz it's just as important as the title when I decide whether or not to click a vid of someone I don't know. It's how I discover new content. Are auto-titles next?