Sometime during the Krita 4 timeline, there was a change where the Sharpness option now forces the brush preview outline to conform to the pixel grid. This kind of behavior is not necessarily preferable to every user/workflow, as I've seen at least a couple users speak against it, so I made this behavior optional and saved to the brush.
By default, this behavior is disabled.
Observe the snappiness of the brush preview outline when:
Also save and test brushes with the above configurations in mind.