Err.. Last time I checked, CUDA was the one with the partially compliant C++ implementation, while, on the contrary, SYSCL was being base on pure C++17..
Time to check again, as CUDA is C++20 for a bit now (minus modules), and NVidia is the one driving the senders/receivers work for C++26, based on their CUDA libraries.
SYCL isn't pure C++, meaning writing STL code that goes into the GPU, like CUDA allows for, nor requires the hardware to follow C++ memory model.
