Canon Watch is reporting that a Canon RF 60mm f/1.0L USM is possibly on the way. This lens does not appear on my RF lens roadmap, nor have we seen any patents for such an optical formula yet.
Is it possible? Sure, why not? If you believe your mount is the best, you need to flex those muscles every now and then.
While it is close to the RF 50mm f/1.2L USM in speed and focal length, I imagine an RF 60mm f/1.0L USM would provide a very unique look to photos. Throw in defocus smoothing and you could have something special.
For now, this is a [CR1] rating, but I will do some digging to figure out the validity of this rumor.