Sharing answers to top q's we’re seeing about the thumbnail experiment: – Custom thumbs aren't going away – 99.7% still see the creator's custom thumbnail – A lot of creators use auto-generated thumbnails, this test helps improve them for those using them: https://goo.gl/A7oDmr
Honestly, it's not great. Even though it negates clickbaity thumbnails, it is REALLY uninteresting to look at recommendations and the sub box without wanting to need to feel initial regret of doing such. The auto-generation COULD be an option, but CANNOT be a default one.