CUDA is the defacto parallel computing platform, and exciting tech moves VERY fast with early mover advantage - so no researcher\computer scientist is going to bother learning another platform or risk\waste time\effort on their stuff breaking when ported to OpenCL\AMD.
Unless a miracle happens, any new parallel-computing requirement that seizes the popular imagination in the next decade (or more) will done in CUDA.
What's taking AMD so long? They just can't do software I guess?
Everything is and always will be some form of lock-in. Look at what’s happened with CentOS or even Ubuntu. Even what was solid open source choices before have turned into some form of exploited lock-in. I’ve come to the realization that it’s impossible to optimize out of lock-in, instead it’s better to cost optimize for current best practices while continuously running test applications on different platforms and technologies when you have the resources to do so.
GPUs are also not super available atm. We'll see if this is a temporary issue or one that persists for years. If you can't get A100s, you'll try the AMD/TPU competitors.