I agree that the issue presented by the article is likely not related to colonialism. More so the disinterest in providing further security resources to the area.
A lot of the Middle East, including Afghanistan, has been affected by the colonial interests of the British Empire in the past. Albeit mostly in the mid to late 19th century and into the WW1 era.
I doubt I understand the nuances to make any claims that the prior issues are indirectly affecting the area currently, but I believe it is worth to note the relation as why it could be brought up in comments.
In this particular situation, the use of deadly force was more so triggered by the fact that the guy was lying about having a weapon and then tries to pull said weapon during a search of his person. The headlock was not the key factor here.