The setting was only affecting some of the blur operations, which
does not typically results in a measurable performance boost in real
compositor setups.
For the simplicity of settings on user level remove setting which
potentially makes compositor output worse, without much benefit.
There are better ways to gain performance, like compositing on a
lower resolution, exposing "preview" as an input to the node tree
(similar to the geometry nodes) etc.
Pull Request: https://projects.blender.org/blender/blender/pulls/121576
9532ea3f8c