Placeholder for update coming on Frozen Realms:
In light of Meltdown and Spectre an update on Frozen Realms by Mark S. Miller is planned agenda for the 63rd meeting of Ecma TC39. March 20-22, 2018 at UCL (London). ecma 
YOUTUBE wQHjITxQX0g Formal Methods meets JavaScript
To clarify JS strict mode is one of several elements added in ES5 (along with Object.freeze, Object.getOwnPropertyNames, ...) that make SES possible as a library. JS strict mode by itself does not turn JS into an ocap system. You still need a library such as SES or the upcoming Frozen Realm shim. -- Cheers, --MarkM
Folks following Frozen Realms. Should review this thoughtful commentary with back and forth Q&A to clarify the spec .