Fortran's array syntax isn't really all that common in HPC codes, in my experience. The initial implementations in the 90's weren't great, and then things got

Fortran's array syntax isn't really all that common in HPC codes, in my experience. The initial implementations in the 90's weren't great, and then things got themselves into a death spiral of HPC codes avoiding features that weren't performance-portable and compiler vendors avoiding work on features that weren't essential to current HPC applications. (This has been a repeated pattern in Fortran since then, too, unfortunately. J3 invents something, often with flaws that go unnoticed until somebody tries to implement it; compilers don't invest in as-yet unused features, especially flawed ones; codes don't use them because they're not portable, or not performance-portable; repeat. DO CONCURRENT is the latest example -- J3 defined it as a serial construct and included semantics that can preclude parallelization...)