Yes, it is true, specially for the regular consumers that don't have any idea of what we are talking about here.
WebGL game engines could already been the new Flash for casual games market, but it is just better, from business sense and support, just to ship native mobile games instead.
Isn't there any application to check for compatibility and enable WebGL hardware acceleration on popular devices? Just like people knew how to install the Flash plugin, they could install this app to set up their browser, and use it as a hub to discover supported games.
WebGL game engines could already been the new Flash for casual games market, but it is just better, from business sense and support, just to ship native mobile games instead.