A drone in the class of predator or orion or Bt2 cost few million dollars. A buk missile is worth destroying them and you have more chance to hit them well before they can use their weapons.
Pantsir S1 in syria proved to be too short on radar detection to be invulnarable against them.
We are talking about big expensive drones.
I think that is the issue... you might have been talking about big expensive drones, but a Terminator wouldn't really get involved with such targets... as you mention BUK and Pantsir would be used against those sorts of targets, not a BMPT support vehicle.
Terminator might be used against close range battlefield drones but would need airburst 30mm cannon shells to deal with them properly.
That is not what I am saying. The discussion here seems to be obsessed with the notion that bull's eye hits from 2 km with such guns is feasible.
For AP ammo they just need to hit a target 2m by 2m most of the time at 2km... which is why the impacts on that target were so close together from perhaps 500m or less.
Against a moving target the idea that you could target the gun barrel or a specific part of the vehicle hull is amusing and of course easy, but actually hitting there on a moving target from that distance is near zero.
Fortunately because it is an automatic weapon a burst of 5-10 rounds should get 4-8 good hits on target most of the time to about 1.5km... at which range it will often penetrate the armour and do some serious damage.
For the HE rounds at 4km range you are firing at area targets anyway...
Yes, 2a42 is highly inaccurate when firing at high rate.
That seemed to be the same bits of video repeated over and over and over.
The burst at about 42 seconds looks like it was fired at the target and corrected with a horizontal sweep to the left rather than inaccurate rounds or gun fire.
The burst from 57 seconds even more so.
Those targets are probably about 1.5km to 2km away.
At high rate it is supposed to be shooting at aircraft and a bit of spread in the shots fired is good when shooting at aircraft as it increases hit probability.