At this point GPU side at least it would require far more than any single misstep to loosen nVidia's hold on the market which extends far beyond consumer interests.But good news for Nvidia haters, nobody is invincible ; a misstep can always happen
The introduction of Intel to the GPU market is one block in that journey, the others may be the gamut of AI/ML players entering the market, which nVidia have by their own hand kind of made all about AI - so the sheer drowning weight of new players may shift the market towards open/interoperable solutions beyond nVidia's CUDA walled garden.
If AMD could work with Intel and/or MS to make a more vendor agnostic non OptiX solution for GPU RT renderers it could also be another blow to knock nVidia down a step or several.
Right now it's too much extra work to put in to implement multiple other GPU RT backends like HIP-RT and Intel's equivalent for the lions share of offline renderer vendors without the kind of direct support that nVidia offers on top of OptiX to sweeten the deal - nVidia is essentially doing almost all of the work for them, so competitors need to band together to break into that market space as one, or stay on the sidelines as many.