It was bound to come to the Canon RF lineup, and now we have a patent for a Canon RF 24-70mm f/4L IS USM. This will go well with the upcoming Canon RF 70-200mm f/4L IS USM.
Canon News uncovered this JPO patent.
Canon RF 24-70mm f/4L IS USM
Focal length: 24.73mm 40.97mm 67.90mm
F Number: 4.12 4.12 4.12
Half angle of view: 41.19° 27.84° 17.67°
Image height: 21.64mm 21.64mm 21.64mm
Total lens length: 145.52mm 135.76mm 160.05mm
BF: 18.00mm 25.64mm 55.54mm