Simple question: if JavaScript in the browser cannot be used to encrypt data --as seems to be the consensus here in this thread--, doesn't it severely limit the

Simple question: if JavaScript in the browser cannot be used to encrypt data --as seems to be the consensus here in this thread--, doesn't it severely limit the usefulness of JavaScript client side? I mean, what can then be JavaScript client-side be used for? Should (could?) SSL have been used to send data "in the clear but encrypted" (including the password to encrypte/decrypt the data) to Mega's servers and then encrypted server-side?