It's also worthwhile to remember that gradually typed languages is /still/ an active research area (MSR has several people working on it, including around ES/TS, and there were adverts for sponsored PhDs around gradual typing in ES/TS around a year ago). I think it's still a bit early to burn something into the standard (once something ships, it'll be near impossible to ever remove; this is probably partly a reaction to ES4 which built a lot on fairly recent and ongoing research, arguably leading to its downfall), but I also think it's a direction most people within the committee want the language to take.
