Since the sidebar view has been the default for some time now, we should have special pixel fitted versions made specifically for it too.
At a glance it might not seem that different but it helps with sharpness especially on the more detailed icons like preferences-smart-status, preferences-system-network-share-windows and preferences-virtualization-container.
Some icons on here could probably be improved but I'm not too sure how to do that without sacrificing some sharpness (preferences-desktop-cryptography, preferences-desktop-baloo)