Looks like this is in the EU only
--- Requirements
To qualify for the entitlement, your app must:
Be available on iOS in the European Union only
Be a separate binary from any app that uses the system-provided web browser engine
Not have the default browser entitlement
[...]https://developer.apple.com/support/alternative-browser-engi...
Given that Congress is in a stalemate, I don't see this coming to the US anytime soon.