We have a product which used to run on Unity Webplayer. After the Chrome NPAPI deprecation we lost about 50% of our users. WebGL wasn't done and still isn't really working. Our experience is the same as described in the article. Memory usage and multi million lines of compressed JavaScript will cause most of our users computers to freeze or lag out. Any user with less than 4 GB and on Chrome will have a pretty bad experience. FireFox is far ahead here and runs much better.

Edit: Direct to one of our games using WebGL and websockets. http://www.kogama.com/games/play/68818/?webgl=1&da=0