My personal view on this is that if we’re going to be breaking source for these attributes, we should review their naming and behavior holistically. They pre-date Swift Evolution and have never been reviewed, and it is unlikely we would break source twice, so such consideration had better be had all at once.
I have never seen a use of @requires_stored_property_inits in the wild, so I wouldn’t characterize this as a “widely known” feature, and the use of “inits” to mean “default value” is entirely unprecedented.
If we are open to a source-breaking change, I would even be open to asking whether @requires_stored_property_inits holds its weight at all or should just be an underscored implementation detail for Obj-C bridging purposes.