For iOS, this is still an issue since the platform disallows JIT. Other platforms can use v8 which will have similar performance with Chrome or Edge.
This really depends on the game, but for iOS specifically, it will be difficult due to the first point.
We looked into it for a bit before and it worked at some point, but no one depends on it and it got broken again after some changes. It hopefully isn’t too difficult to bring back if you want to contribute.