The unrestricted use of implicit conversions is a code smell, which makes several aspects of the Scala type system and type inference fragile and slow. In current Scala 3, conversions require a language import at each use site. I am in favor of tightening the screws further and making use of conversions without that language import an error instead of just a feature warning.
See Proposed Changes and Restrictions For Implicit Conversions
I plan to bring this up as a Pre-SIP soon. We had a long backup of other things that prevented this being proposed sooner. But it’s not forgotten.
In light of all this I am against making implicit conversions more powerful and more of a feature. In particular combining implicit conversions with macros makes me shudder.
Some libraries will have to be rewritten if that’s not longer possible, but that will be a good thing. We collectively need to wean ourselves off this implicit conversion drug. Maybe some specialized idioms will no longer be expressible. If we get a cleaner language with fewer footguns for it I am willing to make that trade.