Indie developers still learning to make games commonly talk about how intimidating shaders are. I used to feel the same way; I remember what it’s like. But now, I encourage everyone to dare writing the simplest shader, to at least understand what precisely they are putting off learning. 
Just playing with colors on a built-in quad with a standard UV map, and skewing vertices around, will teach some devs that shaders themselves aren’t wizard magic. The wizard magic is mastery of the elementary nature of GPU code. There is only a limited number of rigid inputs & outputs, and – tl;dr – the GPU’s design enables developers to weave those inputs together in ever-more-innovative extraordinary ways.
But…a shader is just the programming language doing it, with those few rigid inputs & outputs. The API is shallow. GLSL is friendly, too – https://www.shadertoy.com/ is a testament to GLSL’s accessibility & casual syntax, as something to tinker with.
If you already write code, I insist: complexity is really not an obstacle. 
Picking up an interest in shaders & rendering especially pays off for making games in Defold.
Although it crosses channels, I have not found a better reference for beginners to learn shaders than Godot’s shaders manual. Being written specifically for hobbyists, it is written similarly to learning a new scripting language like GDScript, or Lua:
https://docs.godotengine.org/en/3.6/tutorials/shaders/shader_reference/shading_language.html
It is also GLSL-based, translatable to Defold.
But I feel like shaders put the “video” back into “videogames”, and that makes me happy. There are sound technical & design reasons why so many indie devs like me are reviving effects & techniques left behind when CRT TVs and fixed-function pipelines became obsolete.