I do not think they should be either and my comment stems not from disdain. But sitting in a trench with the enemy converging on your position is not the place to ponder moral dilemma.
On the other hand I just read on Wikipedia that objection to military service on moral grounds is near impossible in Ukraine. This of course puts these people doubly in a position they should not be chastised for.
I imagne that there is ample room for drafted to be assigned to essential noncombat rolles in and outside the military. So a compromise should be possible: Force people into the war effort but not by handing them a weapon.