specifically in this video it might not be an issue and it is really ttk, but I must say after last patch
i experience many hitreg issues. whether it is netcode, hitboxes or something else I don't know.
But I had multiple occasions that I hit an enemy's HEAD, i saw the blood splatter yet he was standing there
like nothing happened. also I had multiple times shooting at someone with no body armor (a tshirt)
in center mass yet he still stood there like i did not hit him.
This (after the last patch) affect all weapons it's just that with sniper rifles you feel it much more.
Unfortunately I don't have any videos but IT'S NOT ttk.