Software Engineers can learn HDLs in one or two weeks about as well as hardware engineers can learn C++ in one or two weeks. Will they get to something syntactically correct? Sure. That doesn't mean what they'd be able to write would be useful. And it's not just the toolchain, it's about understanding that HDL isn't a tool for programming FPGAs, it's a tool for programming hardware and FPGAs are one very specific target for which writing performant code requires a high level of knowledge about the underlying structure of the FPGA.