Honestly, the #1 programming language for parallelization, in practice, is bash scripting. you can convert any single-threaded program into a background thread with the & on the end, and then start running something else.
Yeah yeah yeah, people wanna be complicated with pthreads or async or other features. But... bash's "background" processing (&) gets a surprising amount of things done in my experience. Just spin up a program 300+ times with a & to make them all process in the background, and you're set.
Go is also really good at saturating many cores with its low-overhead goroutines.
For some reason people have the notion that Fortran is still the punch-card days, but Fortran 08 is in fact widely used and quite friendly nowadays. If you're building a very-parallel application that could use something like MPI, you should very seriously consider Fortran.
Others languages such Chapel, Halide probably will do fine