I still use an old pair I got years ago, made by "Bib".
They mostly make a little metal thing used by electronics engineers, but this was when they tried a new model. i bought it at a job stocks merchant who'd bought up their cancelled production.
Imagine a pair of secateurs, where each jaw is blunt but has a sharpened half-moon cutout in it.
Instead of an adjusting screw, it has a rotating wheel to stop the jaws fully closing
This rotating wheel has notches in it. You set the notch to 0.5mm, 1mm, 1.5mm, 2,5mm etc
Put the cable in the half-moons in the jaws, squeeze the handle, they cut through the insulation without nicking the wire, rotate it a bit to make sure, sweep your hands apart and the snibbet of insulation falls on the floor.
The ordinary little "Bib" stripper is still ideal for smaller work, including tlephons and alarms