In the case of the EF 135mm f/2, those who use it know that flat test charts aren't the only measure of a lens' usefulness for taking images of a 3D world. [...] The last thing Canon needed to do was replace the EF 135mm f/2 L with a newer version that produced clinical looking images with nasty bokeh like Sigma's 135. Let the uninformed Philistines rave about how great their Sigma 135s are because they're so good at imaging flat test charts while the rest of us make beautiful photos with our "outdated" EF 135mm f/2 L lenses!
The world could be a nicer place if we would be able to appreciate the value of one thing on its own, without having to degrade another thing in the process.
Do you need to be uniformed in order to appreciate sharpness? Or is it also possible to look at the properties of a product as a whole and judge them in the context of one's own values and use cases?
I don't see anything wrong with the bokeh of my personal Sigma 35 mm 1.4 (Also not in the side by side comparison to the old Canon version
on this site). Nor in the images from the 135 mm I've looked up online. I'm genuinely curious what justifies the negative comments, so if you have a comparison that demonstrates in what way the Canon lens delivers different results, could you please point me in the right direction?
I'm well aware of your point about an increase in sharpness and flat field having affects on other aspects. But I am unconvinced it really has such a large practical impact and the difference is not more a matter of taste than anything else.
The Canon 50mm 1.2 and 85 mm 1.2 RF lenses for instance are also sharp AF and I don't see anything wrong with them. And on the one lens where Canon gave in and added the option to sacrifice sharpness to alter the bokeh, I've not really seen any praise of that feature - I'm talking about the SA control of the RF 100 mm 2.8 L macro of course.