There are so many billions of dollar being spent on this hardware that everyone ...

There are so many billions of dollar being spent on this hardware that everyone other than Nvidia is doing everything they can to make competition happen.

Eg: https://www.intel.com/content/www/us/en/developer/videos/opt...

https://www.intel.com/content/www/us/en/developer/tools/onea...

https://developer.apple.com/metal/tensorflow-plugin/

Large scale opensource is, outside of a few exceptions, built by engineers paid to build it.