if the prize is big enough, there will rise others.
The answer is that the entrenchment of the tools, software and inertia of a defacto standard is what prevents new entrants. The time to stop it is to nip it in the bud. Prevent monopoly from forming, rather than hope that after the monopoly forms, some competitor will break it.
instead, what you have today is this:
> You may not reverse engineer, decompile or disassemble any portion of the output generated using SDK elements for the purpose of translating such output artifacts to target a non-NVIDIA platform.
from https://docs.nvidia.com/cuda/eula/index.html#limitations section 8