I see an starry-constellation effect like this in youtube videos sometimes. It might be some kind of built-in background animation in video-editing software... Whereever it came from we can imitate it from scratch!
The actual method here is based on a Live Coding demo by "The Art of Code" who makes graphics and shader tutorials. "The Universe Within" [Part 1] and [Part 2], our version here is a little more basic and generated a video instead of animated shader.
This took much much longer to create and put into a semi-presentable state than you would think!! Despite already knowing how roughly...