[Ygg2]

No? This happens in any language that has keyword args.

If I delete/rename a field of a class in any statically checked language, it's going to report a compile error, and it's still a breaking change. Same thing with named arguments.

[const_cast]

Sure, but it doesn't actually matter because this can't ever manifest as a bug. Your PR will just be rejected, which to me, is correct behavior.

Typically when you're changing a name you're changing behavior, too. This isn't just something we should let slip under the radar, otherwise bugs can actually manifest.