I agree, they do a great job following the standards. I love that. What I don't love is when they break away. That's my whole point - work with the standards body to get your new cool tech introduced. Don't just go rogue and do whatever you want, that's when problems arise.
"Breaking away" as you describe it sounds like innovation to me, and pacing innovation to standard bodies would kill it. I can't think of specifics but surly most of what is considered the standard today was once the experimentation of one company or one lab.
If Microsoft made ActiveX open and easy for other browser manufactures to implement in a cross-platform manner, I would absolutely have been in support of it. They didn't, so I wasn't.
Standards bodies move slowly. Non-standardised innovation across browsers is absolutely to be encouraged, as long as it is done in a manner that allows others to implement that innovation too. This sort of innovation is what helps us decide what is worth being made into a standard.
Maybe not ActiveX, but when Microsoft created XMLHttpRequest in their javascript engine, that ended up being pretty significant and great for how the web works today.