There are plugins that go back and forth between JSON and YAML so as you might expect it's similar. Unlike JSON, spacing has semantic meaning, which can be a little annoying, especially when cutting and pasting. It's nice in that configs aren't cluttered up with open and close braces. It could be annoying AF if you're a tabs instead of spaces person but idk because I'm a spaces person.

I like YAML for config over .config files but it's not a big deal either way. It just encourages better organization of settings because the hierarchical structure demands it while .config let's you just drop a setting anywhere in the file. But it's valid to have the opposite preference for the exact same reasons.