Do you know how one can get a job as a graphics developer if they know most of these? I do Graphics programming as a hobby, and I learned a lot of what you mentioned here. But since I don't have any job experience, I never really get any interviews.
Always hard to get a foot in the door into a new role when one doesn't have direct company experience in the role on a resume.
The best thing I can think of would be to work on some independent projects (eg. some mod of a game, some indie game or graphics related app itself) and have that work be part of a portfolio.
The other approach that I've seen work is to get into a games company as it is significantly expanding and make it known that you want to do rendering work in the future. At an old company I was at a Gameplay Programmer pivoted to being a Graphics Programmer as the graphics team needed more help and was expanding, and I see via linked in that he's continued in that path.
Streams can tend to be more readable and easier to write for the right problem set. This is because it is super easy to compose basic functions together which are then invoked by the Stream API. It also makes it really easy to parallelize operations.