I think this is just a common Google problem; when you hire A+
level talent they don't want to spend their time adjusting css
for every platform.
In this case, Google plus as a blog, obviously all the platforms are targets. So the CSS should be adjusted for all the platforms, and that must be part of the specs. If you have A+ talent executing, either it will be done, or they haven't implemented that yet according to their priorities, or there is something more unknown to us.