Background
So I see a lot of questions on the site like this. They're all about deeply explaining worldbuilding and stuff, doing all of that explaining type of thing. Normally, I just skip that. For example:
My 'magic' system works by calling upon the power of the ancient tales and old gods.
That's literally all I've said about it. I didn't really want to waste words on going in-depth because there isn't that much to it.
Only details necessary to the story are mentioned.
Now I know this one is going to be particularly frowned upon, but I'm really big on not confusing the reader. I only mention things about the world when they have to be. Of course I have a big, sprawling worldbuilded idea in my head, but I don't want all of that to spill onto the page.
It seems different with a lot of people. Many questions asked on this site are about really in-depth, intense worldbuilding. It all seems so unnecessary to me. For this question I think I'd just have the thing work and mainly show the reader how it worked through dialogue (if I really had to).
Question
A few questions which tie into each other:
Is it necessary to include tons of worldbuilding details?
Will a reader just 'accept' that something works, or require an explanation?
For example, my magic system is a great example of that. There is no explanation for why you can draw upon the power of the ancients it just happens.