[mandarinka]

I'm not sure it's as clear-cut. For example, the alt-ref thing in VP9/AV1 is really a copy of b-frame mechanism that is designed in a roundabout way to not look totally like b-frames, at a glance. Is that an example of "quite happy to avoid IP that's not available under terms they can accept" in a good sense? Sounds more like use the idea but dodge the responsibility to me, but well, maybe they changed enough details to get away with it.
As for the unclearness - it's perfectly possible the patents just weren't discovered or they weren't careful enough in trying to stay clear. I don't think it's a responsibility of patent holder to reach out to everybody in the world to informa them about it, that's pretty much not viable after all.
Also you call a video compression patent a monopoly and paint is as some injustice. But look at it from the inventor's point of view. They invested money and work. They are probably willing to offer it to multiple parties and not having a monopoly. But Google/AOM will only accept it for free. How can you think that refusing to grant the technology to them in such a situation is unjust? AOM's insistence of being royalty free is their choice, they have no right to push that onto IP holders that aren't okay with that. It's normal to want to be compensated for your property/work.

I think we are starting to hijack this thread though, so better stop this debate (which has been here over and over in the past).