This is probably due to my naivety, but it seems like there have been a lot of new libraries recently that are basically "Knockout with slightly different synta

This is probably due to my naivety, but it seems like there have been a lot of new libraries recently that are basically "Knockout with slightly different syntax". But Knockout is robust, well tested, has excellent browser support, has excellent documentation, and is under active development. Why should I be eager to discard it?