If it gets changed into 3-6 it might soon become 100% hit chance since people don't like missing and suddenly the game is undistinguishable from other RPGs out there - a fate I would very much like to avoid.
I think we should be careful to dismiss new players feedback. Especially using slippery slope analogies. It is perfectly reasonable to seek a balance between complete randomness and complete predictability.
That being said, I think your general point is correct. DnDs intricate combat and moderate randomness makes it really engaging. Reducing it could cause it to become easier to plan "optimal" turns and make the combat less interesting.
Sadly, I think DnD suffers from the inherent disadvantages of a dice system at low levels. The randomness feels "just right" when rolling a 3d4 + 4 attack, but can be a bit overkill when hitting for 1d12. Since as the number of dice increase, the probabilities become more and more normalized. (SEE:
https://anydice.com)
This could be subtly tweaked in the RNG at low levels to make a 1d12 distribute more in a bell curve. But I think that might cause more problems then it solves. Either way, this becomes a non-issue after low levels.
