As far as I remember, before A17, you had to aim slightly higher than the head to actually hit a zombie in the head with a melee weapon. Otherwise it would hit the torso.
So it felt like you actually had an arc with melee weapons.
But yeah, I agree. Even though I think the current system is ok and feels pretty nice, melee weapons should be able to connect, be it with lower damage or something, if the target is clearly within the swing arc.
And about the RNG stuff, melee accuracy should not be tied to any skill or perk - it should be purely player skill based for positive melee feel and fluid gameplay. I click, the character swings that way. It is my own (possibly fatal) fault if I clearly miss during intense melee combat. Damage, stamina use, weapon degradation, stun chance etc. are already great ways to have character skill levels influence melee effectiveness.
Ranged weapons have RNG scatter, this is fine. I am not expecting pinpoint accuracy from a pistol I found in the toilet or my low level character to be a world class bowman.