Not really, i think yaml have more capability, you can convert json to yaml 1:1, but the reverse isn't true. But here is the issue: the errors caught in a json

Not really, i think yaml have more capability, you can convert json to yaml 1:1, but the reverse isn't true. But here is the issue: the errors caught in a json-validate won't be in a yaml-validate. If you have 15 inventory file to write per day, you will do a lot of copy pasta, sometimes with errors, and most of those times ansible won't resolve because the yaml was obviously false. The one time it wasn't, it was sadly on a critical part of our infra, and almost cost us a client (and definitely costed trust). Yaml is way more permissive (because it has more capabilities). But we didn't care about map and semi-code or whatnot. If you need it, more power to you, it just wasn't our original usecase. So they wrote some perl json->yaml interpreter with restricted keywords, and after that, the misalignment risk was negated. Ultimately i arrived at the company, was told the story, then wrote stuff to convert excel->json, then SQL->json, and effectively in the end the extra conversion was unnecessary, and probably harder than just converting directly in yaml. I'm not saying yaml is worse than json, i think in 80% of cases, it's better. I'm just saying that in the rare cases where being correct is way more important than being fast, i'd use json.