I had a 35 Zeiss Planar for a while, and that is not smaller.
24, 35, 50 and 85.
I still have the Zeiss 50/1.4 today.
The only smaller lens really is the 35GM....1 out of 4...not a game changer. I don't have the 100mm vs 90mm Macro to compare but it's almost the same. I never got the Sony 135/1.8 so can't compare it to the Canon 135/2.0, I doubt the Sony 1.8 is smaller. The 70-200 GM mk1 I got is not really smaller than then Canon 70-200 L mk1/2/3.
Apples for apples (or as close as you can get), the size and weight are not noticeable, not at all, not even a little bit. To me at least, with these lenses.