The next big step is dependent on JS language/runtime features. Specifically the Record-Tuple proposal (https://github.com/tc39/proposal-record-tuple)

TL;DR: It's a way to designate data as being immutable.

JS doesn't currently have a good way to do this, so everything built for it tries to assume that data hasn't changed since it was last set. This leads to headaches for developers and wasted cycles for runtimes.

When JS has a proper way to make data immutable, it makes it easier for libraries/frameworks to make guarantees about the underlying data and makes it possible for runtimes to better optimize code.