I've got a book here on my shelf which is a summary book of all sorts of approaches in prototype OO programming:
https://www.goodreads.com/book/show/180324.Prototype_Based_P...
From that, and my experience with both Self and with other prototype OO languages (like LambdaMOO & offshoots), I just find the JS implementation to be ... uncomfortable.
Plus from the earliest days people just seemed to be embarassed by the prototype thing. They shouldn't have been.