Learning to program is the most important thing you can do. As long as it isn't web applications everything is fine. Programming isn't really about knowing the syntax of some language or having memorized a list of algorithms, but understanding how to build an appropriate architecture for your system.

>but it seems of dubious usefulness when it comes to finding a job.

There is a very large embedded industry if you want that. Learn about basic electronics as well if you are interested. I highly recommend learning C and (C++ and/or rust) if you want to enter there.

>combinatorial optimization

Nobody in the industry would hire you for that specifically. You might find a role where it is also needed/usefull but it isn't a career path.

>blender/3D modelling

I would absolutely avoid that as a career unless it is a major passion. Maybe you are interested in computer graphics though? That could be an option. Computer graphics is a major industry, video games, professional software for artists or engineering software are some of the larger groups there.

I would focus on R&D positions at large companies or institutions. Engineering positions are more process focused ("do what you are told") and it gets worse the more regulated the industry is (e.g. aerospace).