Object.{get, set}

The optional chaining is one of the core functionality of my proposal. Instead of "optional chaining hell" we can just specify the path we want and get the value if the path exists and undefined otherwise

At least in stackoverflow working with objects by path are popular questions:

And a lot of people trying different solutions which can has bugs and/or performance issues but I believe that native implementation would be the best

Also what do you mean when you say deprecated? Because in the source code they aren't labeled as deprecated: