I think this is a vast understatement. Google has been using their own TPUs for a very long time now. I think they still have some GPUs from Nvidia, but it's marginal compared to their own silicon. Other big players are behind the curve on this front, but very much working to close the gap. These are companies with nearly infinite pockets, Google has shown that you can make it work without Nvidia, it's only a matter of time before others do it too.