Why is Canon RF 85mm f/1.2L USM better than Canon RF 24-70mm f/2.8L IS USM? 57.14% wider aperture at minimum focal length? f/1.2 vs f/2.8

Poised to be the new workhorse zoom, the Canon RF 24-70mm f/2.8L IS USM is a versatile wide-angle to portrait-length lens characterized by its bright, advanced, and intuitive design. The constant f/2.8 maximum aperture suits working in difficult lighting conditions and also enables greater control over depth of field. The optical design incorporates a series of aspherical and Ultra-Low Shoot with confidence even when light levels drop. The RF 24-70mm f/2.8L IS USM is designed to work in conjunction with an EOS R series camera, with both the camera and the lens sharing data to reduce camera-shake blur. With up to 5 stops of Image Stabilization, it delivers impressively clear results when shooting handheld.
The RF 24-70mm F2.8L IS USM, RF 24-105mm F4L IS USM, RF 24-105mm F4-7.1 IS STM, Canon RF 28-70mm F/2L USM and RF 70-200mm F2.8L IS USM, all benefit from a maximum of 8 stops of image stabilisation. Canon claims that the IBIS provides up to 8 stops stabilisation with selected lenses
Canon 首款配備影像穩定器的全片幅f/2.8 標準變焦鏡頭. 適合拍攝風景、新聞、人像及婚禮等題材. 多用途的24-70mm變焦範圍足以應付大部份拍攝題材. f/2.8大光圈及9片圓形光圈葉提供漂亮散景有利營造漂亮柔和散景. 全新研發15組21片光學設計，配備3片GMo玻璃鑄模 非 . 429 415 396 368 247 423 278 79

canon rf 24 70mm f2 8l is usm