Dynamic keys (square brackets on the left hand side in an object literal) have been around for nearly 10 years, if memory serves.

https://www.samanthaming.com/tidbits/37-dynamic-property-nam...

Also in the example is method shorthand:

https://www.samanthaming.com/tidbits/5-concise-method-syntax...

Since symbols cannot be referred to by strings, you can combine the two.

Basically, there isn't any new syntax here.