While SYSCL might stand a chance against CUDA, thanks to it being backend agnostic and a compiler neutral standard, C++ for OpenCL is a clang specific project which remains to be seen if it ever will get any adoption.

> For C++ kernel development, the OpenCL Working Group has transitioned from the original OpenCL C++ kernel language, defined in OpenCL 2.2, to the ‘C++ for OpenCL’ community, open-source project supported by Clang. C++ for OpenCL provides compatibility with OpenCL C, enables developers to use most C++17 features in OpenCL kernels, and is compatible with any OpenCL 2.X or OpenCL 3.0 implementation that supports SPIR-V™ ingestion.

https://www.khronos.org/news/press/khronos-group-releases-op...