YAML 1.2 removed some of the footguns like having five different ways of expressing `true`, but the main Python YAML package is permanently 1.1. strictyaml is

YAML 1.2 removed some of the footguns like having five different ways of expressing `true`, but the main Python YAML package is permanently 1.1. strictyaml is an attempt at tightening things further. But a lot of systems that use "yaml" don't implement any spec, because they write their own parser. For example IIRC gitlab ci doesn't support anchors but has their own code reuse construct. And then there are all of the string templating extensions that projects like Ansible and Helm employ. These in my opinion are far worse than anchors and should be eschewed in favor of a non-static configuration like jsonnet.