Actually it is better for security.
Whenever I visit a WebGL demo inside Linux w/ NVidia drivers, if there are any complicated shaders, my system hard-freezes, forcing me to reboot.
Until the X developers fix Xorg's security model (like that will happen), and until NVidia fixes their Linux drivers (like that will happen), WebGL will always be one massive gaping security and stability problem for me as a Linux user.