Is it possible that you could reconsider making ObjectiveCBridgeable or ReferenceConvertible a public API?
You last looked at it 6 years ago on April 12, 2016 . You reasoned that it's too early to make it a public API:
[…] we feel that it is too early at this point to accept our current design as public API. […] we lack the confidence and implementation experience to commit to
_ObjectiveCBridgeablein its current form as public API.
There are many cases where you might want to bridge a swift struct or class to another ObjC class.
Apple itself uses it in many of their newer code like UICellConfigurationState, INShortcut, PKStroke or UIListSeparatorConfiguration (all iOS 14.0). They are all public APIs. It seems that the bridging is safe to use.