Yes, in my experience this can get to considerable scale (hundreds of thousands and beyond) but at a price. You need to do all your own management for things DOM/SVG were doing (e.g. hit detection, styling). You still need to send the data to the client and probably store it locally (customers will enjoy learning how to start Chrome from the command line with flags like --args --js-flags="--max_old_space_size=8192"). The client environment still doesn't have much support for data management or processing unless you bring in some other JS libraries. I'm a big fan of JS development but the criticism is on target.