Is Rails moving to a YAML (or almost-YAML) parser that does not execute code for future major releases? I find it hard to believe that such functionality is use

Is Rails moving to a YAML (or almost-YAML) parser that does not execute code for future major releases? I find it hard to believe that such functionality is used often. Until then, as the article says, people will just keep finding zero-days. This seems like the only logical choice for the Rails core team.