It's not resolved by, it's mitigated by.
Furthermore, it wasn't mitigated by AMD (or Intel or ARM), it was mitigated by OS / Software vendors that had to spend the time to make workarounds for the hardware's design flaw. It would have been nice to see a nod to such developers for taking the time to help with the problem.
It is easily 6 man-months of work if not double, and the level of expertise necessary to implement this right is pretty high. For a small OS shop, that's a pretty high price.
Free Software projects don't necessarily work like this. It's possible for CPU manufacturers to have taken the lead in the work in Linux, for example. Even just helping (which they have clearly done) is more of a nod than just a nod.