Used it very rarely in the past, in my opinion it could be removed.
Not scope of this thread but in connection with setting parametric masks I want to point to a bug report (affects input and output slider) from june again (Bug : parametric mask, picking GUI color from image, chroma channel). The behaviour described is still present at version 3.3.0+1284~g665fc4d2f, Ubuntu 20.04, OpenCl enabled or disabled.