So YouTube has always been exploited and I'm pretty sure it'll never change. However, the method for doing it changes a lot. A lot of videos that got mobile view boosted or are pretty fake still stand on YouTube. So I'm pretty sure the system checks if you have some view retention where people watch it from a certain amount of time (like with the ranking change.) Most videos that got taken down most likely had many fake views with very few that watched the video for 2/3's of it's duration; so I think it's still possible to view boost once the video has a decent amount of REAL views/likes/comments. Someone said it was about 10% of the views but does anyone have an idea or tested it?