This doesn't really have anything to do with reacting to AMD or their competitive footing(Beyond timing or wording of press releases), different markets, different timescales.
-The fundamental tech behind this Fovoros technology, and the concept of large scale Multi-chip-modules, has been in research or development for decades, and even this specific implementation of interposer stacking would have been many years in the making.
-This hybrid design was done at the request of a third party client for a specific use case and not for competing on the open market, and is for a power envelope AMD was no where near targeting when development would have started(And that's possibly why it did).