[p_l]

The real moat of CUDA is that CUDA... works. Simply works out of the box, even on cheapest GPUs. Unless you want some specific high end stuff, everything will work on the cheapest GPU of given generation, with the same base tooling.

And because of that, their OpenCL implementation also works better than others. So there's more tooling not just from nvidia using it, because it. just. works.

Compare this with AMD, whose latest framework is a total mess of "will it work on this GPU?", sometimes needing custom wrangling to enable, etc. etc. and it's effectively supported only on the most expensive compute-only cards.