> the community doesn't seem to be bothered that for a long time, the only SYCL implementation was a commercial one

Bothered has nothing to do with it. Implementing low level toolchains generally seems to require both a gargantuan effort and an incredible depth of knowledge. If it didn't, I think tooling and languages in general would be significantly better across the board.

What am I supposed to do, implement a SYCL compiler on my own? Forget it - I'll just keep writing GLSL compute shaders or OpenCL kernels until someone with lots of resources is able to foot the initial bill for a fully functional and open source implementation.