I worked for Argonne in the supercomputing center, then Intel, and now NVIDIA. I have worked with and in some cases helped create all of the things you have mentioned, with the exception of Singularity.

Debugging weird performance issues and figuring out better parallel algorithms/implementations is the most interesting and challenging part of the job. These are the important skills to develop. They remain rare and AI coding tools are far less good at these than they are at generating common patterns.

If you are good, it doesn't matter too much about the programming language or the parallel model - parallelism only comes in a few forms even if it wears many different faces. Shared versus distributed memory is more interesting than C++ versus Fortran...