a) A broken reference C compiler don't dictate how a different C compiler might act -- in reference to the case which Intel lost.
b) since Google's browser became the defacto standard browser thanks to Edge switching engines, hence the thread. The standard doesn't really matter anymore; Google makes most of them now as a matter of course anyway.
Google could start responding to YouTube requests with binary streams of gibberish if they want, MS would only have standing to sue as a content creator and advertiser on YouTube.
If Google is reverse engineering other browsers optimization paths and putting out content that is disagreeable to that optimization, that's possibly unfortunate but not illegal.