[Brightcolours]

https://www.sigma-global.com/en/lenses/c..._400_5_63/

For E- & L-mount @ USD 950

Surprisingly it is a little different from the DSLR variant - but just as heavy.

As reference - Canon RF 70-200/2,8 is 1200g  / 1,070g w/o tripod mount. Keep in mind that Canon ware proud of achievement.
Canon premium magnesium casting shaves few grams but Sigma contemporary is not so shabby.

What a strange comparison you try to draw there. Puzzling.

To put things in perspective: The Sigma 100-400mm f5-6.3 weighs... 1140 grams. The Canon EF 100-400mm f4.5-5.6 weighs 1380 grams. They are totally in line, weight wise, when you consider their max. aperture difference.